First, make sure your subscription is still valid. Subscriptions can sometimes fail to renew due to credit card info being out-of-date, etc.
To check, please login at https://www.roverradio.com/my-account/subscriptions/. You should see an Active subscription there. If not, please purchase a new one here.
Please note: subscriptions purchased inside the RoverRadio app will not appear in your Subscriptions list on RoverRadio.com, but you should still have Plus access on the website. If you can access Plus on your mobile device but not the website, please see this help article.
If your subscription is active, please make sure you are logged into the app with the same email/password. Try logging out of the app (click the Settings icon near the top right, then Log Out) and logging back in to verify.
As a last resort, please log out of the apps then Reset Your Password following the directions here.