In Quickbooks Self Employed, how can I undo a invoice payment receipt? Do I just need to delete?

Hey there, peterhenrikson. Let me help you sort this out.

Yes, you can just delete the invoice payment receipt. From the Invoices tab, find the receipt and click the drop-down arrow beside View, then hit Delete.
 

Once deleted, you can follow the steps in this article to re-create the invoice: Create invoices in QuickBooks Self-Employed.

In case you need help with categorizing your transactions in QuickBooks Self-Employed, you can refer to this article: Updates to expense categories in QuickBooks Self-Employed. This will help guide you on how to report your self-employed income and expenses.

Keep me posted if you have any other questions about QuickBooks Self-Employed. I'm always up to keep helping. Have a nice day!