diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
index 4ee1219..4d707e5 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
@@ -13,14 +13,13 @@ import eu.dnetlib.dnetrolemanagement.utils.AuthoritiesUtils;
 import eu.dnetlib.dnetrolemanagement.utils.JsonUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
-import org.springframework.security.access.prepost.PreAuthorize;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.web.bind.annotation.*;
 
 import java.util.Collection;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 @RestController
 @RequestMapping("/admin")
@@ -56,40 +55,52 @@ public class AdminController {
      * Assign admin role to logged in user or user with @email
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.POST)
-    @PreAuthorize("hasAuthority('REGISTERED_USER') || @registryService.getCoPersonIdsByEmail(#email).size() > 0")
     public ResponseEntity<Response> assignRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email) {
-        Integer coPersonId = (email != null) ? registryService.getCoPersonIdsByEmail(email).get(0) : registryService.getCoPersonIdByIdentifier();
-        if (coPersonId != null) {
-            String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+        if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(type, id);
             if (couId != null) {
-                Integer role = registryService.getRoleId(coPersonId, couId);
-                if (role != null) {
-                    if (registryService.getUserAdminGroup(coPersonId, couId) == null) {
-                        registryService.assignAdminRole(coPersonId, couId);
-                        authoritiesUpdater.update(identifier, old -> {
-                            HashSet<SimpleGrantedAuthority> authorities = new HashSet<>((Collection<? extends SimpleGrantedAuthority>) old);
-                            authorities.add(new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
-                            return authorities;
-                        });
-                        return ResponseEntity.ok(new Response("Role has been assigned successfully"));
+                AtomicBoolean assigned = new AtomicBoolean(false);
+                coPersonIds.forEach(coPersonId -> {
+                    if(assignRoleToAccount(coPersonId, couId, type, id)) {
+                        assigned.set(true);
                     }
-                    throw new ConflictException("User is already an admin of this group");
+                });
+                if(assigned.get()) {
+                    return ResponseEntity.ok(new Response("Role has been assigned successfully"));
+                } else {
+                    throw new UnprocessableException("User must be a member of this group and not already admin");
                 }
-                throw new UnprocessableException("User must be member of this group in order to become an admin.");
             }
             throw new ResourceNotFoundException("Role has not been found");
         }
         throw new ResourceNotFoundException("User has not been found");
     }
 
+    private boolean assignRoleToAccount(Integer coPersonId, Integer couId, String type, String id) {
+        String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
+        Integer role = registryService.getRoleId(coPersonId, couId);
+        if (role != null) {
+            if (registryService.getUserAdminGroup(coPersonId, couId) == null) {
+                registryService.assignAdminRole(coPersonId, couId);
+                authoritiesUpdater.update(identifier, old -> {
+                    HashSet<SimpleGrantedAuthority> authorities = new HashSet<>((Collection<? extends SimpleGrantedAuthority>) old);
+                    authorities.add(new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
+                    return authorities;
+                });
+                return true;
+            }
+            return false;
+        }
+        return false;
+    }
+
     /**
      * Remove admin role from logged in user or user with @email
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.DELETE)
-    @PreAuthorize("hasAuthority('REGISTERED_USER') || @registryService.getCoPersonIdsByEmail(#email).size() > 0")
     public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email) {
-        List<Integer> coPersonIds = (email != null) ? registryService.getCoPersonIdsByEmail(email) : Collections.singletonList(registryService.getCoPersonIdByIdentifier());
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
         if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(type, id);
             if (couId != null) {
diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
index b54a864..4ee9e9e 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
@@ -44,7 +44,7 @@ public class MemberController {
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.GET)
     public ResponseEntity<User[]> getInfos(@PathVariable("type") String type, @PathVariable("id") String id) {
         Integer couId = registryService.getCouId(type, id);
-        if(couId != null) {
+        if (couId != null) {
             JsonArray users = registryService.getUserIdByCouId(couId, false);
             JsonArray emails = registryService.getUserEmailByCouId(couId, false);
             JsonArray names = registryService.getUserNamesByCouId(couId, false);
@@ -57,19 +57,20 @@ public class MemberController {
      * Assign member role to logged in user or user with @email
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.POST)
-    @PreAuthorize("hasAuthority('REGISTERED_USER') || @registryService.getCoPersonIdsByEmail(#email).size() > 0")
     public ResponseEntity<Response> assignRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email) {
-        Integer coPersonId = (email != null)?registryService.getCoPersonIdsByEmail(email).get(0):registryService.getCoPersonIdByIdentifier();
-        if (coPersonId != null) {
-            String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+        if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(type, id);
             if (couId != null) {
-                Integer role = registryService.getRoleId(coPersonId, couId);
-                registryService.assignMemberRole(coPersonId, couId, role);
-                authoritiesUpdater.update(identifier, old -> {
-                    HashSet<SimpleGrantedAuthority> authorities = new HashSet<>((Collection<? extends SimpleGrantedAuthority>) old);
-                    authorities.add(new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
-                    return authorities;
+                coPersonIds.forEach(coPersonId -> {
+                    String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
+                    Integer role = registryService.getRoleId(coPersonId, couId);
+                    registryService.assignMemberRole(coPersonId, couId, role);
+                    authoritiesUpdater.update(identifier, old -> {
+                        HashSet<SimpleGrantedAuthority> authorities = new HashSet<>((Collection<? extends SimpleGrantedAuthority>) old);
+                        authorities.add(new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
+                        return authorities;
+                    });
                 });
                 return ResponseEntity.ok(new Response("Role has been assigned successfully"));
             }
@@ -82,14 +83,13 @@ public class MemberController {
      * Remove member role from logged in user or user with @email
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.DELETE)
-    @PreAuthorize("hasAuthority('REGISTERED_USER') || @registryService.getCoPersonIdsByEmail(#email).size() > 0")
     public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email) {
-        List<Integer> coPersonIds = (email != null) ? registryService.getCoPersonIdsByEmail(email) : Collections.singletonList(registryService.getCoPersonIdByIdentifier());
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
         if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(type, id);
             if (couId != null) {
                 // If none of the accounts has admin role for this group remove member role
-                if(coPersonIds.stream().filter(coPersonId -> registryService.getUserAdminGroup(coPersonId, couId) != null).collect(Collectors.toList()).size() == 0) {
+                if (coPersonIds.stream().filter(coPersonId -> registryService.getUserAdminGroup(coPersonId, couId) != null).collect(Collectors.toList()).size() == 0) {
                     coPersonIds.forEach(coPersonId -> {
                         String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
                         Integer role = registryService.getRoleId(coPersonId, couId);
@@ -116,7 +116,7 @@ public class MemberController {
     @RequestMapping(value = "/{type}/{id}/name", method = RequestMethod.GET)
     public ResponseEntity<User[]> getNames(@PathVariable("type") String type, @PathVariable("id") String id) {
         Integer couId = registryService.getCouId(type, id);
-        if(couId != null) {
+        if (couId != null) {
             JsonArray users = registryService.getUserNamesByCouId(couId, false);
             return ResponseEntity.ok(gson.fromJson(users, User[].class));
         }
@@ -129,7 +129,7 @@ public class MemberController {
     @RequestMapping(value = "/{type}/{id}/id", method = RequestMethod.GET)
     public ResponseEntity<User[]> getIds(@PathVariable("type") String type, @PathVariable("id") String id) {
         Integer couId = registryService.getCouId(type, id);
-        if(couId != null) {
+        if (couId != null) {
             JsonArray users = registryService.getUserIdByCouId(couId, false);
             return ResponseEntity.ok(gson.fromJson(users, User[].class));
         }
@@ -142,7 +142,7 @@ public class MemberController {
     @RequestMapping(value = "/{type}/{id}/email", method = RequestMethod.GET)
     public ResponseEntity<User[]> getEmails(@PathVariable("type") String type, @PathVariable("id") String id) {
         Integer couId = registryService.getCouId(type, id);
-        if(couId != null) {
+        if (couId != null) {
             JsonArray users = registryService.getUserEmailByCouId(couId, false);
             return ResponseEntity.ok(gson.fromJson(users, User[].class));
         }
diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java b/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
index 39b1546..60026e1 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
@@ -12,10 +12,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.stereotype.Service;
 
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 @Service
 public class RegistryService {
@@ -39,18 +36,23 @@ public class RegistryService {
      * 1.1 Get CoPersonId by Email
      */
     public List<Integer> getCoPersonIdsByEmail(String email) {
-        List<Integer> coPersonIds = new ArrayList<>();
-        Map<String, String> params = new HashMap<>();
-        params.put("coid", coid);
-        params.put("mail", email);
-        JsonElement response = httpUtils.get("co_people.json", params);
-        if (response != null) {
-            JsonArray coPeople = response.getAsJsonObject().get("CoPeople").getAsJsonArray();
-            for (int i = 0; i < coPeople.size(); i++) {
-                coPersonIds.add(coPeople.get(i).getAsJsonObject().get("Id").getAsInt());
+        if(email != null) {
+            List<Integer> coPersonIds = new ArrayList<>();
+            Map<String, String> params = new HashMap<>();
+            params.put("coid", coid);
+            params.put("mail", email);
+            JsonElement response = httpUtils.get("co_people.json", params);
+            if (response != null) {
+                JsonArray coPeople = response.getAsJsonObject().get("CoPeople").getAsJsonArray();
+                for (int i = 0; i < coPeople.size(); i++) {
+                    coPersonIds.add(coPeople.get(i).getAsJsonObject().get("Id").getAsInt());
+                }
             }
+            return coPersonIds;
+        } else {
+            Integer coPersonId = getCoPersonIdByIdentifier();
+            return (coPersonId != null)? Collections.singletonList(coPersonId):new ArrayList<>();
         }
-        return coPersonIds;
     }
 
     /**