Problem
You have a returned check and need to add a negative NSF check payment to an invoice.
Solution
To record a negative NSF check, create an adjustment invoice and enter the negative payment with the correct payment type. If replacing the payment, add a placeholder task on the adjustment invoice, collect and apply the payment on the original invoice, then delete the placeholder task.
Add negative NSF check payment to an invoice
Create a new adjustment invoice for the invoice you want to correct.
From the adjustment invoice, click Add a payment.
Enter the amount of the NSF check as a negative value.
Select the NSF Check (or equivalent) payment type.
If you want the invoice to show a balance, you are done.
If you want to apply a new payment to the invoice, add a placeholder task for the same amount to the adjustment invoice.
Collect and apply payment on the original invoice.
Delete the placeholder task from the adjustment invoice.
Apply new payment to the invoice
If the customer provides you a different payment method, for example, a credit card, do the following:
Go to the adjustment invoice you created for the returned check.
Add a new payment for the full invoice amount.
Select the payment method.
Enter the payment details.
Apply the payment to the adjustment invoice.
Verify the invoice balance shows $0.00 on the original invoice.
Note: You do not need to delete any placeholder tasks in this scenario if the adjustment invoice already has a zero balance.