Hi there, Erica. 

Allow me to step in and provide some information on how you can change the method of receiving your payment.

Since you're receiving your sales payment through an invoice, you can delete the payment so that the invoice remains open and you can repeat the process with the correct payment type.

Here's how:

1. Go to Sales  and select  Invoices.
2. Find and select the invoice where the payment was applied.
3. Click the View payment link under the Invoice activity section.
4. In the Receive payment page, select More located at the bottom and choose Delete.
5. Hit Yes to confirm.

If you want to link a bank deposit to an invoice you can check out this article:  Link a bank deposit to an invoice

Please let me know if there's anything else that you need help with your QuickBooks Online account. I'll be around to assist you. Take care and stay safe!