The canceled order email - due to payment denied - is not sent. With that, the customer is not aware of the reason why the order was canceled.

To simulate the scenario, you need to use a store that has an antifraud system, make a test order, and ensure that it's denied. Only an email informing that the order has been canceled will be sent.

It is recommended that the canceled order email contain information to guide customers about order cancellations awaiting approval, informing them of the required procedures in case of payment denied.