Apple Music not linking to an existing Apple One subscription

Apple Pay wasn’t working. Forums suggested signing out of Apple ID on the phone and then signing back in.

Not only has that not solved the initial problem, but now I’m unable use Apple Music on my phone even though my ID clearly shows I have Apple One that includes this service.

I can stream music as normal on my AppleTV.

How is this still and ongoing issue when raised by other users 12 months+ ago???

Previous threads stating the ‘pretend to sign up and then cancel’ don’t work. Does anyone know how this stupid issue is resolved?