In some aspects crypto payments work more or less in a similar way to bank transfers. One cannot block the sender from sending more than they should. Depending on your business case or regulatory requirements you might not be able to receive more than a certain threshold, thus you need an option to refund excess/overpaid amounts.
Bear in mind that we'll refund the funds back to source. If the customer is using an exchange they might need to reach out to the support of the said exchange in order to claim the refunded amount.
