diff --git a/apps/dnet-exporter-api/src/main/java/eu/dnetlib/openaire/community/ContextApiController.java b/apps/dnet-exporter-api/src/main/java/eu/dnetlib/openaire/community/ContextApiController.java
index 5e93aca1..145d4b86 100644
--- a/apps/dnet-exporter-api/src/main/java/eu/dnetlib/openaire/community/ContextApiController.java
+++ b/apps/dnet-exporter-api/src/main/java/eu/dnetlib/openaire/community/ContextApiController.java
@@ -6,6 +6,8 @@ import java.util.Set;
 import java.util.stream.Collectors;
 
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.web.bind.annotation.CrossOrigin;
@@ -16,7 +18,6 @@ import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
 import eu.dnetlib.openaire.exporter.exceptions.CommunityException;
-import eu.dnetlib.openaire.exporter.exceptions.ResourceNotFoundException;
 import eu.dnetlib.openaire.exporter.model.community.CommunityType;
 import eu.dnetlib.openaire.exporter.model.community.SubCommunity;
 import eu.dnetlib.openaire.exporter.model.context.CategorySummary;
@@ -38,6 +39,8 @@ public class ContextApiController {
 	@Autowired
 	private CommunityService communityService;
 
+	private static final Log log = LogFactory.getLog(ContextApiController.class);
+
 	@RequestMapping(value = "/contexts", produces = {
 		"application/json"
 	}, method = RequestMethod.GET)
@@ -71,22 +74,27 @@ public class ContextApiController {
 	})
 	public List<CategorySummary> listCategories(
 		@PathVariable final String contextId,
-		@RequestParam(required = false, defaultValue = "false") final boolean all) throws ResourceNotFoundException, CommunityException {
+		@RequestParam(required = false, defaultValue = "false") final boolean all) throws CommunityException {
 
-		return communityService.getSubCommunities(contextId)
-			.stream()
-			.filter(sc -> all || sc.isClaim())
-			.map(sc -> {
-				final String[] parts = StringUtils.split(sc.getSubCommunityId());
-				if (parts.length < 3) { throw new RuntimeException("Invalid conceptId (It should have 3 (or more) parts)"); }
-				final CategorySummary cat = new CategorySummary();
-				cat.setId(parts[0] + "::" + parts[1]);
-				cat.setLabel(sc.getLabel());
-				cat.setHasConcept(true);
-				return cat;
-			})
-			.distinct()
-			.collect(Collectors.toList());
+		try {
+			return communityService.getSubCommunities(contextId)
+				.stream()
+				.filter(sc -> all || sc.isClaim())
+				.map(sc -> {
+					final String[] parts = StringUtils.split(sc.getSubCommunityId(), "::");
+					if (parts.length < 3) { throw new RuntimeException("Invalid conceptId (It should have 3 (or more) parts): " + sc.getSubCommunityId()); }
+					final CategorySummary cat = new CategorySummary();
+					cat.setId(parts[0] + "::" + parts[1]);
+					cat.setLabel(sc.getLabel());
+					cat.setHasConcept(true);
+					return cat;
+				})
+				.distinct()
+				.collect(Collectors.toList());
+		} catch (final Throwable e) {
+			log.error(e);
+			throw new CommunityException(e);
+		}
 	}
 
 	@RequestMapping(value = "/context/category/{categoryId}", produces = {
@@ -101,8 +109,11 @@ public class ContextApiController {
 		@PathVariable final String categoryId,
 		@RequestParam(required = false, defaultValue = "false") final boolean all) throws CommunityException {
 
-		final String[] parts = StringUtils.split(categoryId);
-		if (parts.length != 2) { throw new CommunityException("Invalid category id (it should have 2 parts"); }
+		final String[] parts = StringUtils.split(categoryId, "::");
+		if (parts.length != 2) {
+			log.error("Invalid category id (it should have 2 parts): " + categoryId);
+			throw new CommunityException("Invalid category id (it should have 2 parts): " + categoryId);
+		}
 
 		final String contextId = parts[0];
 
@@ -122,16 +133,19 @@ public class ContextApiController {
 	})
 	public List<ConceptSummary> listSubConcepts(
 		@PathVariable final String conceptId,
-		@RequestParam(required = false, defaultValue = "false") final boolean all) throws ResourceNotFoundException, CommunityException {
+		@RequestParam(required = false, defaultValue = "false") final boolean all) throws CommunityException {
 
-		final String[] parts = StringUtils.split(conceptId);
-		if (parts.length < 3) { throw new CommunityException("Invalid concept id (it should have 3 (or more) parts"); }
+		final String[] parts = StringUtils.split(conceptId, "::");
+		if (parts.length < 3) {
+			log.error("Invalid concept id (it should have 3 (or more) parts): " + conceptId);
+			throw new CommunityException("Invalid concept id (it should have 3 (or more) parts): " + conceptId);
+		}
 
 		final String contextId = parts[0];
 
 		final List<SubCommunity> list = findSubCommunities(conceptId + "::", all, contextId);
 
-		return processSubCommunities(contextId, list);
+		return processSubCommunities(conceptId, list);
 	}
 
 	private List<SubCommunity> findSubCommunities(final String prefix, final boolean all, final String contextId) throws CommunityException {