Apple Music Family Sharing not recognized on Android

Hi all, I'm having a hard time trying to run the Apple Music app on an Android phone with version 13. I've added my Brother to my family sharing option, and he accepted the invitation on his Android, but when he opens the app, with the right account settings, the app only shows the options for free trial, or gives him the option for a subscription. We reset the app, reset the cache, and even took him out of the family sharing option and added him again. But unfortunately, none of the previous actions works.

Any other idea?

Thanks in advance!

Diego!