Requesting signatures in Firefox - Dropbox loggs me out multiple time in a session

Dear community,

here is my issue:

Dropbox logs me out of the browser (Firefox, Chrome, Opera) multiple time during one session.

I need to log in to access my documents to request a signature.

The "remember me" button is ticked.

When I need to select the savefolder I appear to be logged out again, I try to log back in and end up in a never ending loop.

I tried multiple browsers, VPN off and on, checked my settings, emptied my cache.
When I am lucky it works after restarting the process multiple times.

What can i do to solve this issue?

Thank you.

All the best