Does a Dental Office have an obligation to tell you they are going out of network when you have been a patient for four years in-network?

Question

I had been going to a dentist from 2018-2022. I had work done in the summer and fall of 2022. They treated these appointments as normal - collected my copay, did the work, filed with the insurance, etc. In January of 2023 they called to tell me that the insurance company had repeatedly denied the last two claims and asked if I would contact the insurance company to help. The insurance company said that the dentist office had fallen out of network. The dentist office tried to blame it on the insurance company and the insurance company has made it very clear it was the fault of the dentist office. The insurance company said they would pay the two claims in good faith. Nine plus months later the insurance company has not paid the claims. I have spoken with three people at the insurance company over those months that have said yea they will pay but they keep kicking back. The dental office is looking at me to pay the bill. Did the dental office have any kind of obligation to inform me that they would be falling out of network? I never would have had the work done with them had I known that. This is in the state of Virginia if that matters. Thanks!