Hi busterboo367
Thank you for your post. You can write off the invoice as a bad debt. To write off a bad debt, you enter a negative value sale to create a credit note that can be used to close the sale you won’t be receiving payment for. This enables you to adjust the customer's balance. This Help Article, Accounting for bad debts, has more detailed information that you can use as a guide.
Please feel free to post again. I'm happy to assist further.
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