Works for me too, with Findroid 0.15.3 on jellyfin server 10.11.1, did a clean install just to test for OP.

If the app was still installed and logged in when upgrading to latest major version of jellyfin server, the other poster might have to clean cache on the app. I had to do this for all my current jellyfin android app sessions, otherwise it wouldn't connect to the new jellyfin instance after I upgraded