COBRA Insurance Question

I became permanently disabled 17 months ago and enrolled in COBRA so I could continue having healthcare coverage. After 5 months, I stopped paying my COBRA premiums and switched to Medicaid because I can no longer work and can’t afford the high monthly payments. I assumed that the COBRA plan would be automatically terminated due to non-payment when I stopped paying for it. That is what the contract said when I enrolled. Unbeknownst to me, this was not the case.

This month, my doctor prescribed me a medication. My doctor had my Medicaid information on file, but my pharmacy billed the COBRA insurance plan. This is how I found out it was still active. I called the insurance company (BCBS) and asked if they could deny the claim and they said no. They said that because of a new rule due to COVID the grace period was extended by one year and my insurance stayed active the entire time. I am now being billed several thousand dollars for the retroactive cost of COBRA, back to the last date I paid for it a year ago. The medication would have been fully covered by Medicaid had the pharmacy billed them instead. Am I stuck paying thousands of dollars for a medication that should have been free now, or is there any way around this problem? I’m in California.