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In other words, if the customer’s pre-paid card is declined because of insufficient funds then at the third attempt the customer is not going to receive the 50% discount as before.
Please note that:
For regular orders and extended free trials, if customers paid with Credit Card, the 50% discount is still applied at the third attempt.
For pre-order, the 50% rule, at the third attempt, is not applied to any card (prepaid or regular credit card).