After you made the changes, did you scroll down and click save on each page until you got all the way through the report? If not the changes may not have actually saved.
I save each page until the entire report goes through, and then I use the email feature on the specific report to tell them that the changes have been made. I do that because like you, the first time I wasn't saving and they called me weeks later to see when I was going to fix the report. Now I never have any issues.