I paid for Pro but it is not active. What now?

Give it a minute, then reload the app. After checkout the app polls for about 20 seconds and unlocks by itself, and a reload re-checks Pro status on launch. If the payment landed but activation lags, a banner says "Payment received but Pro activation is taking longer than usual" - that state resolves itself in nearly all cases. In store builds, a purchase that fails to validate retries when you restart the app, and a purchase that never activates is refunded by the store automatically within 3 days.

Still locked? It is almost always an account mismatch: Pro attaches to the account that was signed in at purchase, so a different phrase - or a provider login instead of your phrase vault - is a different account. Compare the Account ID under Settings > ID & Sync on the device that bought it. If it is genuinely stuck, report it and include that Account ID: it identifies the purchase and reveals nothing about your notes.