Refund for overpayment in California—how much time do providers have?

Hi, I live in California and paid an imaging center a $200 deposit for an ultrasound. My insurance EOB says my responsibility is $0 and they paid the imaging center one month ago. The imaging center is now dragging their feet in issuing a refund to me.

I see the California Business and Professional Code 732 addresses refunds of duplicate/overpayments to doctors and dentists, but does an imaging center fall under this category? Just wondering how much time is reasonable to wait for a refund before I escalate (although I’m not sure who I’d escalate to other than filing a chargeback on my credit card).

(a) A physician and surgeon and a dentist shall refund any amount that a patient has paid for services rendered that has subsequently been paid to the physician and surgeon or dentist by a third-party payor and that constitutes a duplicate payment. The refund shall be made as follows:

(1) If the patient requests a refund, within 30 days following the request from that patient for a refund if the duplicate payment has been received, or within 30 days of receipt of the duplicate payment if the duplicate payment has not been received.

(2) If the patient does not request a refund, within 90 days of the date the physician and surgeon or dentist knows, or should have known, of the receipt of the duplicate payment, the physician and surgeon or dentist shall notify the patient of the duplicate payment, and the duplicate payment shall be refunded within 30 days unless the patient requests that a credit balance be retained.

(b) Violation of this section shall constitute unprofessional conduct. Disciplinary proceedings shall be conducted in accordance with the Medical Practice Act (Chapter 5 (commencing with Section 2000)) or the Dental Practice Act (Chapter 4 (commencing with Section 1600)), as applicable.