How to record a customer duplicate payment as a credit

Ensuring that the overpayment is accurately recorded as a credit is my priority, layasdad.

When you receive an overpayment on a customer's account we can create a credit if you've set up customer credits to apply to future payments by default.

Here's how:

1. Navigate to the Sales section and choose Customers.
2. Choose the specific customer to whom you wish to allocate the credit.
3. From the dropdown menu labeled New Transaction ▼, opt for Payment.
4. Complete all the necessary information.
5. Click on Save and Close.
6. A warning message will pop up stating "You didn’t select any invoices". Afterward, choose Save as a credit.
7. Go to Transactions and select Bank Transactions.
8. Associate the payment with the previously generated credit.

You have two option to apply the credit to an invoice, you can check this article for the step-by-step guide:  Handle a customer credit or overpayment in QuickBooks Online. 

If your customer considers an overpayment a tip, you can view this article for the steps: Record an invoice overpayment as a tip.

Feel free to respond to this message if you have any additional queries about a customer's overpayment. I'm here to help. Have a great day!