MS Teams on Iphone spreadsheet not showing all columns

Starting 09/08/2020 we are no longer able to view the entire Excel fil in Teams on iOS devices within Teams. Previously we were able to view out to column NJ, currently we can only view data out to column IV.
The file size is less than 150KB.
All the columns still show on Android phones or on a computer. It's just the iPhones that are having the problem.
The file was uploaded from computer (My Docs), not from DropBox or OneDrive.
We have tried:
- Clear cache on iPhone
- Force Quit on teams app
- checked for latest version of iOS.
- installing MS Office for iPhone application

This is for all iOS users. Not just one.
We have tried reuploading the spreadsheet after checking it on the computer.
It is working on android devices if I open the Excel application.
we also tried "hiding" columns - still will not show past column IV.
we did not modify any settings.
we have also tried downloading, renaming and uploading with the same results.
this is occurring for iPhone X and 11.