diff --git a/src/Handler/Corrections.hs b/src/Handler/Corrections.hs
index e97f93c9e..99d7510b5 100644
--- a/src/Handler/Corrections.hs
+++ b/src/Handler/Corrections.hs
@@ -366,13 +366,13 @@ assignAction :: Either CourseId SheetId -> ActionCorrections'
 assignAction selId = ( CorrSetCorrector
                      , wFormToAForm $ do
                          correctors <- liftHandlerT . runDB . E.select . E.from $ \(course `E.InnerJoin` sheet `E.InnerJoin` sheetCorrector `E.InnerJoin` user) -> do
-                           E.on $ user E.^. UserId E.==. sheetCorrector E.^. SheetCorrectorUser
-                           E.on $ sheet E.^. SheetId E.==. sheetCorrector E.^. SheetCorrectorSheet
+                           E.on $   user E.^. UserId   E.==. sheetCorrector E.^. SheetCorrectorUser
+                           E.on $  sheet E.^. SheetId  E.==. sheetCorrector E.^. SheetCorrectorSheet
                            E.on $ course E.^. CourseId E.==. sheet E.^. SheetCourse
 
                            E.where_ $ either (\cId -> course E.^. CourseId E.==. E.val cId) (\shId -> sheet E.^. SheetId E.==. E.val shId) selId
 
-                           return user
+                           E.distinct $ return user
 
                          mr <- getMessageRender