After I log in to Sync, it asks me to log in again and again
When I log into Firefox Sync on my Android Fairphone, it says "you can now use Sync". But when I open sync it wants me to log in again, no matter if i open it via Firefox or via Accounts on my phone.
On the Xiaomi phone I want to transfer the data to Sync works just fine. I have checked the version, it is 54.0.1 on both phones. I also have tried closing the browser on both phones and I have deleted the account and re-created it on the other phone, nothing of which helped. After re-creating the account, the Fairphone doesn't show up in the devices list anymore either, even after I "logged in" several times...
Any idea what could be wrong there? Thanks in advance for any help!