Resigned but Hospitalized: Can I Still Claim Insurance for My Hospital Stay?

I resigned from my previous employer on Nov 4th and was relieved on Jan 4th. I have insurance coverage until Jan 4th, 2011. I was hospitalized from Dec 26th to Dec 30th, and I had claimed insurance for it on Feb 2nd, 2011. The insurer is denying my claim, stating that I submitted the claim after resignation. Is my claim valid? Would I be able to challenge this legally? Please advise.

It is legally valid to be paid unless there is a claim submission timeline that you may have breached.

Regards,
Deepak