diff --git a/src/main/java/org/gcube/portal/oauth/OauthService.java b/src/main/java/org/gcube/portal/oauth/OauthService.java
index e2bc9de..ab79677 100644
--- a/src/main/java/org/gcube/portal/oauth/OauthService.java
+++ b/src/main/java/org/gcube/portal/oauth/OauthService.java
@@ -171,7 +171,7 @@ public class OauthService {
 			String errorMessage = checkRequest(clientId, clientSecret, redirectUri, code, grantType);
 			if(errorMessage != null){
 				logger.error("The request fails because of " + errorMessage);
-				return Response.status(status).entity(new AccessTokenErrorResponse(errorMessage, null, null)).build();
+				return Response.status(status).entity(new AccessTokenErrorResponse(errorMessage, null)).build();
 			}else{
 				logger.info("The request is ok");
 				String tokenToReturn = entries.get(code).getToken();
@@ -182,7 +182,7 @@ public class OauthService {
 		}catch(Exception e){
 			logger.error("Failed to perform this operation", e);
 			status = Status.BAD_REQUEST;
-			return Response.status(status).entity(new AccessTokenErrorResponse("invalid_request", null, null)).build();
+			return Response.status(status).entity(new AccessTokenErrorResponse("invalid_request", null)).build();
 		}
 	}
 
diff --git a/src/main/java/org/gcube/portal/oauth/output/AccessTokenErrorResponse.java b/src/main/java/org/gcube/portal/oauth/output/AccessTokenErrorResponse.java
index fc4e621..affe976 100644
--- a/src/main/java/org/gcube/portal/oauth/output/AccessTokenErrorResponse.java
+++ b/src/main/java/org/gcube/portal/oauth/output/AccessTokenErrorResponse.java
@@ -1,7 +1,5 @@
 package org.gcube.portal.oauth.output;
 
-import javax.validation.constraints.NotNull;
-
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 /**
@@ -10,16 +8,12 @@ import com.fasterxml.jackson.annotation.JsonProperty;
  */
 public class AccessTokenErrorResponse {
 
-	@NotNull
 	@JsonProperty("error")
 	private String error;
 
 	@JsonProperty("error_description")
 	private String errorDescription;
 
-	@JsonProperty("error_uri")
-	private String errorUri;
-
 	public AccessTokenErrorResponse() {
 		super();
 	}
@@ -29,12 +23,10 @@ public class AccessTokenErrorResponse {
 	 * @param errorDescription
 	 * @param errorUri
 	 */
-	public AccessTokenErrorResponse(String error, String errorDescription,
-			String errorUri) {
+	public AccessTokenErrorResponse(String error, String errorDescription) {
 		super();
 		this.error = error;
 		this.errorDescription = errorDescription;
-		this.errorUri = errorUri;
 	}
 
 	public String getError() {
@@ -53,18 +45,11 @@ public class AccessTokenErrorResponse {
 		this.errorDescription = errorDescription;
 	}
 
-	public String getErrorUri() {
-		return errorUri;
-	}
-
-	public void setErrorUri(String errorUri) {
-		this.errorUri = errorUri;
-	}
-
 	@Override
 	public String toString() {
-		return "AccessTokenErrorResponse [error=" + error
-				+ ", errorDescription=" + errorDescription + ", errorUri="
-				+ errorUri + "]";
+		return "AccessTokenErrorResponse ["
+				+ (error != null ? "error=" + error + ", " : "")
+				+ (errorDescription != null ? "errorDescription="
+						+ errorDescription : "") + "]";
 	}
 }