Entries cannot be edited on the Bill due to applied payments. To edit the Bill, first unapply all of its payments

Problem:

When editing a pre-bill, client gets an error message that says:

Entries cannot be edited on the Bill due to applied payments. To edit the Bill, first unapply all of its paymentspre

Or:

There was a problem editing the billing entry. Billing Entries cannot be changed on Bills with Payments, Credits or Refunds

Solution:

This will mean that there is some sort of payment/credit applied. The best way to unapply this payment/credit without reversing the payment is to go to the bill and click on Bill Actions > Payment/Credit History:

If there are any payments/credits applied, it will show on this window. Just unclick the box next to that payment/credit and click "Apply" in the lower right hand corner.

At that point, the payment/credit is no longer applied to the bill. Go back to the pre-bill and Centerbase should allow edits at that point.