I can't open an Excel document stored in Dropbox through my iPad Pro.

Someone posted this and it works for me. 

Just use the Files app and connect it to your Dropbox, then access the Files app within Microsoft Office or any other application. It's a much better experience, for any cloud storage service.

I removed Dropbox from Excel "Storage Accounts" and then retried opening the file directly from Dropbox into Excel.  It still almost works and then at the last it pops up anther login box for Dropbox and automatically dismisses it half a second later before you can even do anything and then says it fails.  It's almost like Dropbox is requiring/requesting that Excel log in twice and the credentials don't persist after the first time.

AGAIN, I have a video (screen capture) of all of this and you can see with your own eyes what's happening if you'll just tell me how to get you a link to download it.  Can you email/message me directly?  I don't want to post the link on here for the whole world to see.  I'm trying to help you help me! 😃