Hi Charmarsh Years ago there was a problem where if someone kept the "thanks" page open in their browser then another email would be sent every time they refreshed the page but now a check is made and only one email is sent. What payment processor were you using and is it a custom setup?
I am using PayFlow Pro and PayPal Express. The customer getting repeats used PayPal Express. I also do get other duplicate email authorizations from time to time.
Hi Charmarsh I get the feeling that you should really be thinking of upgrading to PayPal Checkout - Advanced Cards and if this is the case it should give you all the advantages of the new PayPal Checkout integration and solve this issue on the way. But could you check with PayPal that this is the upgrade path for you?
PayPal said it would be no problem but when I changed it and tried to checkout I got a bunch of errors: "No value passed to payment at ...paypalobjects.com/api..."