Business ProfileforRadNet Plano Texas

I had an MRI performed on 1/17/22 at Lenox Hill radiology. I received a call the morning of the procedure saying that my insurance was not working - I explained to The person Who called that my insurance was fine and that I would call my insurance co to resolve the issue. I was told that if I arrived for my appointment with an authorization # that the procedure would go ahead and my insurance would be billed directly. When I arrived, I was made to pay out of pocket, even though I had the authorization number I was told that the procedure would be canceled if I didn't pay upfront and I was having surgery and could not reschedule. I was given a bill which I submitted to my insurance company but the claim was denied as the bill didn't have a diagnosis code or procedure code. I requested a new bill with the proper codes but never received it. Meanwhile, when I called Radnet about the bill, I was told that as Lenox Hill radiology is in network w my insurance company they were responsible for getting reimbursed and would send me a check for the 849.00 I was owed. I followed up with Radnet a number of times and was told that it would take 40 business days for my check to be processed. After more than 40 days I received a letter from Radnet saying they reviewed my account and "taken action to resolve my concerns" There was no check and no contact info. I called Radnet again and was told that my insurance co denied payment because of untimely filing- the next person said this was not correct and they'd look into the issue and call me back w in /4 hours- I never received a call back. I've called Radnet 9 times now, each time being pot on hold for 16-48 minutes. I've requested a callback from a supervisor 4 times and have never received one. On my last two calls I asked to be given the name and contact info for someone from customer service and the VP of the co and was told that this info was not available. I'm at a loss for how to proceed