Does it happen to 1 particular book, or any/all books?
Can you open a new instance of excel, click File - New etc...
Does it work in a new blank book?

I'm not clear if the book you posted (with my name as the filename) was supposed to represent the problem, or what you attempted based on my post.

I wasn't telling you to put in that custom format...
I was saying that custom format may already be there causing you to not see..


Can you post another book showing the problem "As-Is", before attempting any fixes that have been suggested here.