Individual health plan lapsed – says it won’t cover costs in between? What to do?

I have had my health insurance on auto pay for many years and never missed a payment. Perfect record. A couple months back they switched their auto pay system and it needed to be reset up. I did immediately, all good.

Then I left the country for several weeks for vacation, and unfortunately got Covid, and have spent several weeks recovering from a bad go of it. Needed to go to ER once for very concerning chest pains and got a CT scan. All normal. Thank God for insurance, right?

Well, I just got a piece of mail today saying my health insurance coverage had lapsed and was terminated for non payment for 45 days. I had no idea. This was the only piece of mail I received. (Maybe another was sent but lost or thrown away?).

I searched emails and no email was ever sent either.

The letter says they can reinstate my insurance, but any services during the time of lapse will not be covered. This would mean I would have something like a $10k non insured ER bill coming my way.

Im both furious and scared. How can they cancel health insurance without so much as a phone call, or multiple letters of warning? Or more time than 45 days? Especially right after changing their entire auto pay system?

Is there anything I can do about this, or any recourse? Am I going to be stuck with the health bills incurred since reinstatement? Their offices don’t reopen until Monday so I’m sweating bullets and pretty upset at being blind sided like this.