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I am testing my application in the Sandbox. My understanding about the BuyerPaymentTransactionNumber that in the SoldReport is that it is the PayPal Transaction ID. Is my understanding correct?
The BuyerPaymentTransactionNumber returned in the SoldReport does not match with PayPal Transaction ID in the Paypal buyer test account.
SoldReport snippet -
PayPal buyer test account snapshot -
The BuyerPaymentTransactionNumber returned in the SoldReport is the PayPal TransactionID. It is the same as the ExternalTransactionID returned by GetSellerTransactions.
However, the PayPal TransactionID for an eBay transaction is not the same for the seller and buyer paypal account. You are observing the mismatch because you are looking at the buyer's paypal account. If you look at the seller's paypal account you will see that the BuyerPaymentTransactionNumber matches the TransactionID in the seller's paypal account.