Hi there
Please try this
Check Family Sharing: Ask the family organizer to verify that your account is still active in their Family sharing group and that the main subscription payment went through.
Re-enable Subscription: If the family plan lapsed, the organizer must update their payment method so the subscription renews.
Turn On Sync Library: Go to your iPhone Settings, tap Music, and make sure Sync Library is turned on. If it is already on, try toggling it off and back on again.
Re-verify your Apple ID: Make sure you are signed into the exact same Apple Account you used to set up or share the subscription.