Purchases fail in a few distinct ways, and Tollgate tells you which one you hit rather than shrugging. Here is what each message means and what to do.
The purchase failed before completing. No money moved. Common causes: a payment method Apple could not charge, a network drop mid purchase, or an App Store hiccup. Check Settings → your name → Payment & Shipping if it repeats, then try again. Nothing to clean up.
Nothing happens, on purpose. No charge, no nag, no guilt modal. The paywall closes and the free tier continues being free forever.
The rare and annoying one: Apple confirmed the charge, but the entitlement did not land on your device in that moment. Your money is not lost, the record of the purchase is safely attached to your Apple ID. To reconnect it:
The paywall could not load prices from the App Store at all, so no purchase was possible and nothing was charged. Tollgate keeps working meanwhile. Try again when your connection settles.