The target '%1!s!' of the MERGE statement has an INSTEAD OF trigger on some, but not all, of the actions specified in the ...

The target '%1!s!' of the MERGE statement has an INSTEAD OF trigger on some, but not all, of the actions specified in the MERGE statement. In a MERGE statement, if any action has an enabled INSTEAD OF trigger on the target, then all actions must have enabled INSTEAD OF triggers.