New orderNumber is generated everytime payment is initiated

[MichaelNielsenDK]

Whenever a client goes to the payment gateway, a new orderNumber is generated.

This can cause issues, where clients pay on the "wrong" orderNumber, and will give the same transationId but different orderNumbers in Vendr and in the Payment Gateway.

When going through checkout, on the final step before payment, CTRL click on the button that sends you to the payment, so it will open in a new tab.

Here I've CTRL clicked twice, and opened two new tabs https://prnt.sc/15h3z00

The order in Vendr will now have the orderNumber from window 2, but if I go through payment in window 1, the gateway will get the orderNumber from window 1.

The payment will go through and the callback will work, as there is no check on the orderNumber property in the callback. The transactionId will be added to the order.

My suggestion is, that when an orderNumber has been generated on an order, this never changes again.