Preventing Duplicate Orders

We’ve had two “duplicate orders” from new customers in the past few days. This is on a Woocommerce installation tied to PayPal as our processor. We have not heard from our customers yet regarding what they experienced.

What I can say is that the orders are back-to-back, and while most historical references to problems like this relate to site traffic, the bottom line is that I don’t think “high traffic” is necessarily the culprit on our end (yes, I know it’s the holidays, but our analytics shows that for this particular property, the traffic levels remained well within our normal range of activity). It certainly seems possible that Paypal may have failed to relay the appropriate success information, causing customers to resubmit their orders…no doubt PayPal themselves is probably seeing tremendous traffic.

Both sets of duplicates came in first as guest checkouts, then with known accounts. The first ones were 4 minutes apart, and both were paid. The second set was 16 minutes apart, and again, both paid.

I cannot find any instances of this happening in recent history (e.g. this year), which suggests this is a new or isolated problem.

So, that said, while I may not be able to determine why these duplicate orders were created, what else can I do to prevent them? E.g. is there a plugin that will scan all orders in the past 24 hours, for example, and compare to one that’s being submitted, and flag it so that the user has to truly say “yes, I want to submit this order again”? Anything else we can do?