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A: Those buttons appear stacked, because they are a single widget element that is injected into the checkout by PayPal.
Q: We are seeing OrderID’s for some transactions in PayPal that have letters at the end of the orderID, what is causing this to happen?
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A: We have to make the order id unique in PayPal. The transaction process for orders that contain an accepted upsell after offer, is that we void the first transaction when someone takes an upsell that causes a change to the order total for the final PayPal charge. So, this change to the orderID would indicate a voided authorization, that is replaced by another transaction.
Related Documentation
PayPal API Transaction Responses: https://developer.paypal.com/api/nvp-soap/errors/