Random orders after paypal payment no back office order created

[seekyourgeek]

Prestashop v1.6.0.14  

Paypal USA, Canada v1.3.9

So far this year this website had had almost 2,000 total orders. Of those 2,000 roughly 12 orders are having problems, and typically the same customers each time. 

Front end- They will add items to their cart. Go to checkout. All info entered and they get forwarded to paypal to pay. After successful payment they get forwarded back to the website, however all items are still in cart.

Back end- I can see their cart under their account and it is marked abandoned.

Paypal-  Paypal shows what items and qty are ordered. It shows the total and payment that came through. 


Typically they reach out to us saying it happened, we go in and manually create their order from their cart. We then select payment approved. 
 

Any suggestions?