Health insurance companies won’t pay, please help

I am a college student and saw various medical providers throughout 2020-2021 while I had two medical insurances, B through my school and A through my parents. When I went to a provider in late 2020, they (wrongly) told me B was my primary insurance, and I stupidly believed them, so there were many of my services which were billed to B instead of A first. Recently, B realized this error and has gone back to each provider to request their money back for the services, asking that A pay their portion before B does. However, A is now claiming that these services are outside of their billing timeframe, so they won’t pay. Now, the providers are sending me the bills, and I don’t know what to do. I’ve tried filing an appeal with A but they’re saying that part of their agreement with in-network providers is that they can’t bill patients outside of their 180-day timeframe, but they’re billing me anyway. The total of these services are well over $60k, which I definitely do not have. I don’t know what to do now. I’m afraid they’ll send the bills to collections. Is there anything I can do to help my situation?