Voiding Payments
If you enter a payment in error, you can void the payment from the payments recorded screen. You do need permission to void a payment.
Voiding a payment will re-open that amount as a receivable and could re-open an invoice, if that was the only payment recorded.
You can void payments from the recorded payments page. Go to Billing > Payments Recorded and search for the payment you want to void.
The Actions column has a trash can icon that can be used to void/delete payments. The payment will read as voided and you can enter in a reason for the void as well.
When a credit card payment is voided, it will cancel the actual transaction if the void happens the same day. Otherwise, the void will only remove the record of the payment. You will have to do a refund through your payment processor.