No, you can try but the ability will either crash WCIII, work as normal or fail to work completely. The bug is also completely random and i don't know anyone who's found a way to reproduce it.
Just delete and remake the ability. It occurs every now and then, i've had it occur several times in WEU, never happened in normal WE however, so that may have something to do with it.
Like i said, i've never had this trouble in the normal editor after years of using both object and campaign editors. I can only suggest reloading the ability and recreating it, if the bug persists, restart the editor, that worked for me with WEU.