Apple Music is not synching on IPhone

Hello,

I recently subscribed to Apple One. Apple Music seems to work on my new iPhone 14 and my MacBook Air but for some reason my older iPhone 11 doesn't recognise the subscription even though I am logged in with my AppleID.

I saw other people have similar issues and the answer provided was not solving my problem unfortunately.

I tried the following which did not help:

• Restart devices
• Turn off synching library on all devices then turn it back on
• Check if I have still space on my old iPhone
• Delete Apple Music App from the old phone than reinstall it
• Log out of Apple Music on my old phone and log in again with my AppleID

Since the iPhone 11 acts like I have no subscription it tells me to Join Apple Music and pay. In the Settings/Music menu doesn't even offer the option to turn on Synch Library.

Any ideas how to get around this problem?