A patient receives a routine check-up, and the office visit is billed at $150. The patient's insurance company processes the claim and pays $120, which reflects the agreed contractual rate for the service. The patient had already paid a $50 co-pay at the time of service. How should the medical assistant process the overpayment in the patient's account?
Apply the credit balance to future visits.
Transfer the credit balance to another patient's account with an outstanding balance.
Issue a refund to the patient for the overpayment.
Write off the credit balance as an adjustment.