So I've seen a client for the first session, classified them as self-pay, created an invoice, and they paid it with credit card through client portal. I wasn't credentialed with their insurance company but now I am. The insurance company is allowing me to submit charges for the session I had with him and charged him as self-pay. Should I delete the invoice he paid? Will that create a credit for the account, and then be applied to the copay for that session and the second session? How does this work?