Business ProfileforAccurate Medical Billing

I had surgery on 12/13/2021, and was double covered with Cigna for insurance. My primary insurance had met the deductible and everything was covered at 100%, I reached my out of pocket *** in July 2021. The surgical assistant submitted a claim to my insurance on Feb. 2022, which more information was required before it could be paid. The insurance requested my medical records in order to process the claim. I hadn't heard anything after that. The primary insurance cancelled out on 1/1/2022 because it was under COBRA due to my father passing away. No EOB or anything was sent for this. Feb. 7, 2024 I was sent a bill for $350 for the surgical assisant. 3 years later I am being billed for something that should have been covered at 100%. The Insurance can't even fix the claim because it is passed the 180 day billing window. I've called and left messages with AMB to get this cleared to no avail. No one answers the phone or calls back. The Insurance couldn't get ahold of them either. Reading reviews it appears they will not call at all and will send the file to creditors.