When troubleshooting a customer’s claim that their balance is incorrect, it can help to simplify the view of their history. Go to the History tab of their customer information window. Click to make sure you’re seeing a view of their history that shows a running balance. Next, click , then click , and finally click . With this view of the customer’s charges and payments you can now see if they missed a payment, were charged for an extra service, were mistakenly double-charged, or had some other discrepancy.
Help Files - . . . a Customer Claims Their Balance is Incorrect?