I can help you with that, @Little Colorado LLC. 

You can create and send a transaction statement to your customers. This way, they'll be notified the credit has already been applied to the invoice. Here's how:

1. Go to the Sales menu and select the Customers tab.
2. Select the checkboxes for the customers you want to make statements for.
3. In the Batch actions dropdown menu▼, select Create statements.
4. In the Statement Type dropdown menu▼, select the customer statement type:
   • Balance Forward or Transaction Statements
5. Select the dates for the statements and the date range.
6. Review the customer's email addresses.
7. Select Save and send.

I've added these handy related articles for additional information about customer statements: Create and view customer statements.

Let me know if you have further questions or concerns. You can reach out to the Community at any time.