If a regular transaction fails, you will be notified of the unsuccessful attempt, and offered a Grace Period™ to make the payment and keep things on track. Learn more about Grace Period™ here.
It is important to note why the transaction has failed, and what to do about it.
Most commonly, transactions fail due to the following:
Insufficient funds - Always ensure the account you use is appropriately funded.
Voided/Blocked - Certain card issuers (banks etc) have restrictions on what cards can be used for. Please check with your bank if you receive a failed response to ensure your card can be used for recurring transactions.
G501 - Payment Method Suspended - This will occur only after a previous failed transaction where the payment was not permitted by the card issuer (as above). The payment method within Paypa Plane is now suspended, and in order to lift that suspension, you will need to contact Paypa Plane at email@example.com.
You can find the fail code by logging in to your Paypa Plane account (either via the app, or at client.paypaplane.com) and clicking the appropriate agreement, then history and selecting the transaction that failed to view payment details (see image below).