The app was not correctly configured and cannot access your Dropbox

I have exactly the same problem - "The app was not correctly configured and cannot access your Dropbox". However, I didn't change anything - did not upgrade to Android 12 nor change phones. I have Samsung Galaxy S21 and some time last week syncing just stopped working. I have a paid Dropbox account (so the devices limit can not be the problem here), and a paid version of 1Password.
I tried removing "1Password for Android" from the list of authorized apps in Dropbox, and then launched 1Password again - it showed a dialogue asking to authorize, but after I clicked "authorize" it showed the same error message again. I tried to uninstall and re-install 1Password and Dropbox apps - not only it did not fix the problem, but it actually made worse, because now it can't even download the vault and shows the same error, so I don't have access to my passwords on my phone.
Note that I also tried deleting Dropbox apps to force 1Password to use the web auth flow - this way, I get to the point where I'm asked which account to give 1Password access to (personal or work) and when I click "personal" nothing happens.
Could someone from the support please escalate this to get it fixed, as there's simply no workaround for this issue.