diff --git a/src/CollaborationSession/collaborationsession.schema.ts b/src/CollaborationSession/collaborationsession.schema.ts
index 361e2b0..16b36a1 100644
--- a/src/CollaborationSession/collaborationsession.schema.ts
+++ b/src/CollaborationSession/collaborationsession.schema.ts
@@ -99,6 +99,8 @@ export class CollaborationSessionSchema extends PothosSchema {
             //     },
             //   })
             // }
+            // check if user is participant
+            if (!collaborationSession.collaboratorsIds.includes(ctx.http.me.id)) throw new Error('User not allowed')
             return collaborationSession
           }
           /* ---------- use case 2 : center mentor get collaboration session by schedule date id --------- */
diff --git a/src/common/utils/datetime.utils.ts b/src/common/utils/datetime.utils.ts
index 6a2ff6f..301867b 100644
--- a/src/common/utils/datetime.utils.ts
+++ b/src/common/utils/datetime.utils.ts
@@ -73,9 +73,9 @@ export class DateTimeUtils {
 
   static fromDate(date: Date): DateTime {
     const dateTime = DateTime.fromJSDate(date)
-    if (!dateTime.isValid) {
-      throw new Error('Invalid date time')
-    }
+    // if (!dateTime.isValid) {
+    //   throw new Error('Invalid date time')
+    // }
     return dateTime
   }