PayPal IPN notification receiving multiple notification for the same payment
Two posibilities came to my mind:
- PayPal retries notification, if your handling script returns HTTP error.
- For certain transations PayPal sends multiple notifications. Like for cheques. Or when transaction is later cancelled/refunded/reversed. You need to check payment status field for that.
It looks like a very old post but i find this same issue on 2019and you can simply fix this by adding
header("HTTP/1.1 200 OK");adding http header 200 ok in first line of your code.