How do I delete/ unpair my Invoice App from Quick books?

Look no further, @alec-bloom-hotma.

Are you referring to a third-party app that is connected to your QuickBooks Self-Employed account? If so, I recommend consulting our technical support team to assist you to delete/unpair the app from QBSE. To do so, please refer to these steps:

1. Go to the Assistant menu.
2. Enter your concern "Delete/unpair my Invoice App from QuickBooks."
3. Then, type Talk to a human.
4. Choose either  Message an agent or Get a callback.

Also, I've added this helpful article in case you'll need to disconnect your bank accounts in QuickBooks Self-Employed: Delete bank and transaction data in QuickBooks Self-Employed.

Then, to help you manage and track your business income and expenses, please see this link: QuickBooks

Self-Employed Overview. 

Feel free to post again here if you have further concerns about managing your QuickBooks Self-Employed account. I'm always here to help. Have a good one.