Please follow the steps to restore your Pro access on our website:
If you already have an Ultimate Guitar account:
1) Check which UG account you're using in your mobile app
2) Log in to the same account on our website
If you don't have a UG account yet:
1) Open the mobile app
2) Tap "account&settings" > "create account"
Your Google Play subscription will attach to your UG account and you'll be able to use it on the website.
Note: Purchasing a subscription does not create a UG account for your automatically. Your subscription is attached to your Google Play account and your UG account should be registered in the app.