SAP Message 37764 - You cannot change container in modification mode

Diagnosis
You tried to move the element into another container. This would haveconstituted an invalid modification, since the change would not havebeen compatible with the existing flow logic.

System Response
The element could not be moved.

Procedure
If required, create a new element in the target container. You cannotdelete the element you wanted to move, but you can use the LOOP ATSCREEN statement in the screen flow logic to make it invisible.