Barium Enema After Incomplete Colonoscopy

Our office performs barium enemas after an incomplete colonoscopy. Our billing company is using diagnosis code V64.3, which makes sense for coding the colonoscopy itself, but not so much the BE. To me, anyway.

The claims are being denied using this V64.3, but I'm having trouble coming up with a better diagnosis to use. Is this diagnosis appropriate?

Any help with this is appreciated!

Barium Enema After Incomplete Colonoscopy