iOS/Dropbox not working no matter what I do

Is your computer running MacOS or Windows?

If I had read the earlier posts more carefully, I would have realized you had said you are on a Mac. My apologies.

Two things you can check:

Under System Preferences → Apple ID → iCloud make sure “Optimize Mac Storage” is off

Also under the Dropbox Preferences menu → Sync make sure Smart Sync is set to not “Save hard drive space automatically”.

Screen Shot 2022-06-18 at 3.34.19 PM

Either (or both) of these could cause issues.