Lost insurance 7 months ago but kept receiving benefits? Now confused when it comes to taxes etc.

So I lost my job June 1st of last year and from that time until current have still received my prescriptions at their insured rates, ~$3/month and ~$8/month respectively. During that period I also logged into the United Healthcare portal and it showed me still having coverage, along with receiving monthly statements etc under me old employer.

Now, finally since we’re in a new year I suppose, I log in and get a different homepage saying my coverage from my work ended at the end of the month I was let go, 6/31, and that a new coverage plan that I must have been put on automatically ended 7/31.

To be clear my intent was never to try and “fly under the radar” thinking I was still on my old work’s insurance and that they just forgot to take me off. I called United a week after being let go to get my options, and was told there was nothing to do because I still had coverage. I called again July and they said I had no change in coverage. In September I received an email saying I had a statement to view. I couldn’t view it with out logging in, couldn’t log in as my account was under my work email, so I called and they helped me log on, set new email, etc, I found the statement which simply said a doctor’s visit had been paid in full (was from a standard doctor visit with $50 copay.) So throughout this time nothing changed and it still showed me as on the PPO Gold plan which my work had.

So anyways, now when I logged in today it shows what I presume is the actual string of events with regard to my change in employment status and plan types over the course of those months. Regardless, any and all coverage I had ended 7/31 but as of last month prescriptions still got filled as normal with no hiccups whatsoever.

So that brings me today when the pharmacy is finally having an “insurance issue,” I know exactly what the issue is. I have no coverage. But I’m not clear on what I need to do in terms of taxes this year as I assume I’ll now be on the hook for paying for not having insurance for 4 months. I don’t understand if this was just United not updating my account for a long period of time, mistakes made by previous employer, or what, but I was regularly checking my status, and everything I needed from my insurance coverage kept working, so I didn’t let it worry me too much. My new job starts Feb 1st so not really planning on getting any supplementary/market insurance between now and then, and the issue with the pharmacy will obviously be resolved then, but there are a fair few questions that still remain…