Health insurance EOBs say I owe $0, but hospital is still billing me thousands

I did an intensive outpatient mental health program through a hospital a few months ago. It was all telehealth, which is covered at 100% by my insurance with $0 member responsibility. I kept getting bills from the hospital despite my EOBs saying $0, so I called and reminded them of this. They told me that they billed it as regular instead of telehealth because “the service is normally in person,” but I managed to find a contact number for them in another state and they were happy to rebill as telehealth.

Since then, I’ve gotten more EOBs saying I owe $0. I’ve also gotten bills totaling thousands of dollars from the hospital.

I can no longer connect with anyone at the hospital or this number in another state (I can’t find it on google anymore and it’s not on the bills; I had to dig for it). No one returns my voicemails asking to help me resolve this issue, and I haven’t paid them because my health insurance says I owe nothing. My health insurance said I need to talk to the provider, but they won’t answer me. What can I do from here?