I have successfully loaded doc's from Dropbox but it has suddenly stopped working. I am not aware of making any changes to Dropbox or the iPad in general. The following two screen shots show the error messages.
Did you recently update to iOS 13.7?
Are you using the latest version of the Dropbox app?
On iOS 13.7, updated Dropbox and now all working well. Many thanks for the prompt attention.
Grant N
Great.