diff --git a/src/Utils/Lens.hs b/src/Utils/Lens.hs
index 5e5f993c6..4c00b0231 100644
--- a/src/Utils/Lens.hs
+++ b/src/Utils/Lens.hs
@@ -260,8 +260,6 @@ makeLenses_ ''ExamOccurrence
 
 makeLenses_ ''ExamOfficeLabel
 
-makePrisms ''AuthenticationMode
-
 makeLenses_ ''CourseUserNote
 makeLenses_ ''CourseParticipant