Apple music glitch?

Hi there, I just got a new Apple Iphone 13, upgraded from an 8. My Apple Music is not downloading and I keep getting a error message:

Too Many Devices To Play offline content, you'll need to remove some devices from your account.

I pay for the family plan and only have 3 users on it. Everything was fine until I transferred to my new phone.

Thank you for your help.

Oh Ya, and my phone shows up as Iphone (6) what does the (6 mean)?