It's good to see you here in the thread, @awilp.

You can create a check or journal entry and link it to open credit by utilizing the Receive Payment function. This way, it will offset the credit without the need for issuing an invoice. I know how to achieve your goal. I'll share it with you.

When your customers don't have an open invoice and they still have a credit from you, you can still zero it out by issuing a refund. Let's manage this smoothly by recording a check. I'll show you how:

First step is creating a check.

1. Go to Banking and choose Write checks.
2. Select the customer's name in the Pay to the order of.
3. Choose Account receivable in the Account. Put the amount then enter the customer's name in the Customer: Job and tap Save.

You can now link the refund.

1. In the Customers, click Receive Payments.
2. Use the same customer in the Receive from.
3. Tick your created check as it will show up in the available credits. If done, hit Save and close.

Alternatively, you can make a journal entry by debiting the account receivable, selecting the correct customer, and crediting the corresponding offsetting account. For more information about this process, check out this guide: Write off customer and vendor balances. To ensure that everything is accurately recorded, I recommend consulting your accountant when performing this procedure to ensure that everything is accurately recorded.

Moreover, I encourage you to reconcile your checking account in QBDT regularly to monitor your income transactions. As a reference, see this article: Reconcile an account in QuickBooks Desktop.

Achieving your business goals same as applying a credit without an invoice is our task here in the Community space, @awilp. Feel free to be back again when concerns are still up in your mind. Keep safe!