diff --git a/physics/views.py b/physics/views.py
index e5264164..310c7ef4 100644
--- a/physics/views.py
+++ b/physics/views.py
@@ -323,7 +323,7 @@ def exam_take(request, pk, sk, cid, passcode=None):
         raise Http404("Exam not found")
 
     if exam.valid_users.exists():
-        user = exam.valid_users.filter(cid=cid)
+        user = exam.valid_users.filter(cid=cid).first()
 
         if not user or user.passcode != passcode:
             raise Http404("Exam not found")