Unable to download software instruments

1. I picked up a new M1 MacBook Pro (Monterey 12.5) last week, opened up GarageBand (10.4.5).
2. Opened the software instrument panel on the left, clicked to download several instruments. They started downloading.
3. I was prompted by The Apple Music Content Installer to enter my username and password. I entered those.
4. Got a pop-up: "GarageBand was not able to install the new sounds. Close and re-open GarageBand to download and install them again."
5. When I quit, I get another prompt: "Are you sure you want to cancel the download?"
   1. If I hit Continue, I get the list of software instruments, some failed, some downloading, some idle.
      1. If I quit again I go back to #4 above
   2. If I hit cancel, the application quits.

Now whenever I open GarageBand, I'm in that loop. I can open an existing project or create a new one but I can't download new software instruments. The panel of downloading instruments is still there in the background but the downloads never finish; as soon as the meter on the first one completes, I get the prompt at #3 above and the cycle continues.

I know I'm entering the right password. Is this a known issue? Should I re-install Garageband?