fix

server/controllers/representationController.js

@@ -283,8 +283,12 @@ module.exports.add_representation = [
       data.representation_code = representation_code
 
       const representation = new Representation(data)
-      await representation.save()
       const user = await User.findById(user_id)
+      if(!user){
+        res404(res,"آین کاربر در دیتای ما وجود ندارد")
+      }else{
+        await representation.save()
+      }
       user.askedForRepresentation = true
       user.representation_code = representation_code
       await user.save()

server/models/Representation.js

@@ -11,7 +11,7 @@ FilesSchema.virtual('url').get(file)
 
 const RepresentationSchema = mongoose.Schema({
   // user info
-  user_id: { type: mongoose.ObjectId, ref: 'User' },
+  user_id: { type: String, ref: 'User' },
   representation_code: String,
   agent_code: String,
   editAccess: { type: Boolean, default: false },