diff --git a/src/Handler/Utils/Users.hs b/src/Handler/Utils/Users.hs
index 1a5e6a033..f5ed9107f 100644
--- a/src/Handler/Utils/Users.hs
+++ b/src/Handler/Utils/Users.hs
@@ -870,30 +870,38 @@ assimilateUser newUserId oldUserId = mapReaderT execWriterT $ do
   deleteWhere [ UserCompanyUser ==. oldUserId]
 
   -- merge some optional / incomplete user fields
+  let mergeBy :: forall a . PersistField a => (a -> a -> Bool) -> EntityField User a -> (Bool, Update User)
+      mergeBy cmp uf =  let ufl   = fieldLens uf
+                            oldV  = oldUserEnt ^. ufl
+                            newV  = newUserEnt ^. ufl
+                        in (cmp oldV newV, uf =. oldV)
+                        
+      mergeMaybe :: forall b . PersistField b => EntityField User (Maybe b) -> (Bool, Update User)
+      mergeMaybe = mergeBy (\oldV newV -> isNothing newV && isJust oldV)
+
   update newUserId [upd | (True, upd) <-    -- NOTE: persist does shortcircuit null updates as expected
-      [ ( isNothing (newUser ^. _userLdapPrimaryKey) && isJust (oldUser ^. _userLdapPrimaryKey)
-        , UserLdapPrimaryKey =. oldUser ^. _userLdapPrimaryKey )
-      , ( newUser ^. _userAuthentication > oldUser ^. _userAuthentication
-        , UserAuthentication =. oldUser ^. _userAuthentication )
-      , ( newUser ^. _userLastAuthentication < oldUser ^. _userLastAuthentication
-        , UserLastAuthentication =. oldUser ^. _userLastAuthentication )
-      , ( newUser ^. _userCreated > oldUser ^. _userCreated
-        , UserCreated =. oldUser ^. _userCreated )
+      [ mergeMaybe UserLdapPrimaryKey
+      , mergeBy (<) UserAuthentication
+      , mergeBy (>) UserLastAuthentication
+      , mergeBy (<) UserCreated
       , ( not (validEmail' (newUser ^. _userEmail       )) && validEmail' (oldUser ^. _userEmail)
         , UserEmail =. oldUser ^. _userEmail)
       , ( not (validEmail' (newUser ^. _userDisplayEmail)) && validEmail' (oldUser ^. _userDisplayEmail)
         , UserDisplayEmail =. oldUser ^. _userDisplayEmail)
-      , ( isNothing (newUser ^. _userMatrikelnummer) && isJust (oldUser ^. _userMatrikelnummer)
-        , UserMatrikelnummer =. oldUser ^. _userMatrikelnummer )
+      , mergeMaybe UserMatrikelnummer
       , ( isNothing (newUser ^. _userPostAddress) && isJust (oldUser ^. _userPostAddress)
         , UserPostAddress =. oldUser ^. _userPostAddress )
       , ( isNothing (newUser ^. _userPostAddress) && isJust (oldUser ^. _userPostAddress)
         , UserPostLastUpdate =. oldUser ^. _userPostLastUpdate )
       , ( (isJust (newUser ^. _userPostAddress) || isJust (oldUser ^. _userPostAddress))
           && (newUser ^. _userPrefersPostal || oldUser ^. _userPrefersPostal)
-        , UserPrefersPostal =. True )
-      , ( isNothing (newUser ^. _userPinPassword) && isJust (oldUser ^. _userPinPassword)
-        , UserPinPassword =. oldUser ^. _userPinPassword )      
+        , UserPrefersPostal =. True )      
+      , mergeMaybe UserPinPassword
+      , mergeMaybe UserLanguages
+      , mergeMaybe UserSex
+      , mergeMaybe UserBirthday
+      , mergeMaybe UserTelephone
+      , mergeMaybe UserMobile
       ]
     ]