1. If the payment is not yet posted, select File, Delete from the menu
     
  2. If the payment is posted, Void the payment

    Note: If you have the optional module Cash Management, you will be prompted to select whether to reduce the total deposit amount or create an offsetting bank adjustment. Select the option that is appropriate for your organization.

    If you do not have Cash Management, you will only have the option to reduce the total deposit amount

Possible Alternative Solution:

Enter a negative payment.