If the bank transfer fails and the back up funding source (card) fails then that can cause a negative balance on PayPal. However when you are in the checkout, every time you will be able to choose the funding option for the transaction, card or bank. It just can't be set permanantly as the card. When you have a negative balance it isn't as much of an issue as it is with the bank, there are no charges like going into an overdraft. As long as you resolve the negative balance as quickly as you can. But this is only if both funding sources fail on the account. Hope this helps! 🙂
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