I edited customer info on an invoice, and now all of my invoices have changed the customer info. How can I change it back?

Welcome to the QuickBooks Community, @wilko10. Let me provide insights into changing a customer's details on an invoice in QuickBooks Self-Employed (QBSE).

When editing a customer's information on an invoice, it changes the customer record itself, which affects all the invoices. To change it back, please refer to the steps below:

1. Go to Invoices.
2. Locate the invoice and click Edit.
3. Select Edit customer info.
4. Update the details as necessary, then Save.
5. Click Save.

If you need to use different customer information for a specific invoice, I suggest creating another customer profile. To do that:

1. On the Invoices page, click Create Invoice.
2. Select Add Customer, then + Add New.
3. Enter the necessary details.
4. Click Save, then Save again.

Furthermore, here's an article for your guide in collecting sales tax for the products and services you sell in QBSE: Manually track sales tax in QuickBooks Self-Employed.

Keep in touch if you have other questions about changing customer details in QBSE. The Community team is here to assist you anytime. Stay safe.