Podcast Bookkeeper Sync Constant Sign In

My mom started getting this constant sign-in request from Podcast Bookkeeper Sync, even though she doesn't listen to podcasts. It may have started when she mistakenly clicked on an NPR podcast link. Seems like this is a common question.

The solution was simple, though it took an hour to track down: this is an endless loop authorization error between the Podcasts app and iTunes or Music. We solved it by logging into Music in our case, could be iTunes in your case. That's it.

You may see advice online about changing the user ID. Podcasts crashed whenever we tried to access the Account menu, until we launched Music. Then Podcasts started behaving. It seems like Music/iTunes is the master.

References:

https://discussions.apple.com/thread/251231504

https://www.reddit.com/r/podcasts/comments/a57s7t/is_apple_podcast_connect_loginlooping_anyone_else/