Employer Terminated Dental and Medical Insurance Months Ahead of Layoffs

I worked for a small tech company that was doing pretty bad financially and was subsequently laid off on 11/29. My last day of healthcare coverage was 11/30. Prior to me getting laid off, I received a letter from my healthcare servicer informing me that my coverage was terminated in September. I emailed my employer twice and received no direct response or explanation.

Yesterday, my dentist reached out to me over a cleaning he did in August, informing me that my company insurance was terminated in July. Apparently, the insurance company paid the amount and retracted a few days ago due to my employer terminating coverage in July.

P.S. neither of these cases were during open enrollment time either. I checked ADP and I was still paying for medical, dental, vision, etc monthly until my last day employed.

I’m worried I am going to have to pay out of pocket for all of these services that happened during my employment.

Curious if this has happened to anyone and what would be some good next steps.