We have been getting some paypal duplicate payments Using paypal express checkout and keep having to refund customers.
I read the link below and logged in paypal to make sure the setting was to NOT allow duplicate invoice numbers which it was, but upon checking it seems the invoice/order number from cs cart has been appended from 987654 to 987654-2 in paypal so paypal doesnt see it as a duplicate invoice, and takes 2 payments.
Does anyone have an idea if it is CS that is appending the invoice number or paypal?
https://www.paypal.com/cs/smarthelp/article/how-do-i-avoid-duplicate-transactions-ts1097