@katerberg It depends on which subscription tier you originally purchased. If you go to Ivory's settings on your phone and then tap on the Manage Subscription button, it should take you to your sub details in the OS Settings. If you are on the iOS + iPad OS tier, you will need to upgrade. If you are on the iOS + macOS tier, it should work.
@ivory ah, didn’t realize that I bought the app only on one device :-/