I have a sales receipt that I want to remove the payment from and turn into an invoice, how do I do that?

Since invoice and sales receipt are fundamentally different types of transactions, direct conversion is not an option in QuickBooks, Regina.
 

In this situation, we'll have to note the items and details on the receipt, then delete it. Then, re-enter it as an invoice.
 

Here's how to delete:
 

1. Go to the My apps menu, then Sales & Get Paid.
2. Navigate to Sales transactions.
3. Modify the Type, Date, and Customer fields to locate the entry instantly.
   
4. Click the sales receipt's designated dropdown arrow beside the Print option.
5. Select Delete.
   
6. Once prompted, confirm the action by ticking the Delete button.
   

Once done, record it as an invoice by referring to the original details from the sales receipt. If paid, manually enter its payment.

However, if the sales receipt is matched to a bank transaction (payment from a customer), you'll have to unlink it first from the Posted tab:

1. Go to the My apps menu, then Accounting.
2. Navigate to Bank transactions and select the appropriate bank account.
3. Click the Posted tab and locate the entry to which the sales receipt was matched.
4. Tick the transaction's designated Checkbox and choose Undo.
   

Then, follow the steps to delete the sales receipt and enter it as an invoice. After that, you can re-match the bank transaction to the newly created invoice.
 

Don't hesitate to reply to this thread whenever you need assistance.