Regarding the modification of a payment, you can find two different scenarios:
A. Modify or delete a payment method from an order in progress.
1. First of all, go to the payment screen.
2. On the bottom left will appear the payments you have already made.
3. Swipe to the left the one you want to delete (red key) it or modify (blue key) it.
4A. In case case you want to change the payment method select Modify and replace it.
4B. In case case you want to delete it just select Delete and start again.
4A. Modify
4B. Delete
B. Modify a payment method from a closed order
1. Go to Settings ⚙️ (at the top right) > Orders.
2. Choose the closed orders section.
3. Select the order with the wrong payment method.
4. Then, it will lead you to the payment screen again.
5. Once there, on the bottom left will appear the payments you have already made.
6. Swipe to the left the one you want to modify it.
7. To change the payment method select Modify and replace it.
Remember that you cannot delete a payment from a closed order. In order to cancel a payment from a closed order you should cancel the whole order and note it down again.
If you want to see how to cancel an order, please click here.