diff --git a/app/models/remote_evaluation_mapping.rb b/app/models/remote_evaluation_mapping.rb
index 8f6f6192..551ab8a6 100644
--- a/app/models/remote_evaluation_mapping.rb
+++ b/app/models/remote_evaluation_mapping.rb
@@ -2,7 +2,7 @@
 class RemoteEvaluationMapping < ApplicationRecord
   before_create :generate_token, unless: :validation_token?
   belongs_to :exercise
-  belongs_to :user
+  belongs_to :user, class_name: 'ExternalUser'
 
   def generate_token
     self.validation_token = SecureRandom.urlsafe_base64