The Payments section of the Customers menu shows a list of all the payment activities that have occurred for this customer. It can include both automatic payments (if there is a credit card on file and an invoice has been auto-collected) as well as manual payments. Refunds are also handled under Payments.
Note: If you are using Fusebill Hierarchy, and a payment was made using a parent payment method, it will be indicated under "Method" with the parent/child icon ().
The Invoice(s) column shows the list of invoices that were paid off with this payment, if applicable. If there is only one invoice its number will show in the column; otherwise click on the small bars to pop up a list: