How to test buyer side of a Credit Card transaction on PayPal Website Payments Pro?

Question

We are running an e-commerce web site on Ruby on Rails and for the processing of Credit Cards we use the ActiveMerchant plugin to interface to our PayPal Website Payments Pro account using our API credentials.

As part of the checkout process we first call the authorize function on our gateway object and then, after some further checks, we perform the capture part.

We have lately been experiencing a bug where an amount gets reserved twice on a customer's account: one charge being only the authorization and the second being the final purchase. So to the client it looks like we are billing him twice (once for authorization, once for final purchase) while we are actually receiving the money only once and the "second charge" on his account is simply an authorization that we don't clear for some reason. (This seems to happen particularly when PayPal FMF rejects our transaction and we re-process.)

I am trying to troubleshoot this by creating PayPal Sandbox Accounts for Buyer and for Seller. I am running through the code line by line via Rails Console and simulating different conditions to try and replicate the error. However, my successful Credit Card transactions only appear in my "seller"/"merchant" account and not in the "buyer" account on the PayPal Sandbox so I cannot see what the effect of my code sequence is having on a customer's card. This post seems to indicate that that is just the way things are and that it is indeed not possible to test the effect on Buyer Credit Card side. This post suggests using PayPal Express Checkout but that is not what we need on our site as we're specifically looking at Credit Card transactions here that are integrated to our site.

How can I test the effect of my code on a client's Credit Card? Is there perhaps something I missed in PayPal or is there maybe some mode/log/monitor in ActiveMerchant that I can use to see this? I need to find the line of code that is causing us to authorize twice.

Answer 1

If the initial transaction is being rejected by FMF, and then you reattempt another transaction this would cause a second hold on the buyers card as this would be a completely different transaction attempt. The bank may have approved the first transaction, but then the FMF filters declined it based on your settings. As far as the bank is concerned, it is still a valid charge that was approved. So when you run your second attempt, this will cause a second hold on the card for the same amount but for a different transaction.