Am I legally covered if my employer withholds money but doesn't pay insurance co?

I thought I signed up for the family dental plan at work 4 months ago. After my husband's dental claim was denied, I was told that I checked the wrong box (employee/child box) on my application. I did list my husband's name, his SS #, etc. in the list of covered dependents, but the insurance co. says they go by the box that was checked. My employer has been deducting the amount for the family plan from my paycheck. My employer just sent me a check for the difference between what was deducted from my paycheck for the family plan and the employee/child plan. I don't think this is fair, since my husband's dental bill is more than that. I think my HR rep dropped the ball by not catching the discrepancy on the application. She obviously knew I wanted the family plan since that is what is being withheld from my check every pay period. Evidently my employer is deducting for the family plan but only paying the insurance co. for employee/child coverage. How do I proceed?
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Well, this is a fuzzy area. You're going to have to complain to your state insurance commissioner, in writing. And they'll ask for the insurance company to defend themselves. The insurance company will produce the application with the box checked, and I think that's going to be their defense. I think the employer has fixed their error, by refunding you the additional amount. I think you're going to have to wait until open enrollment, to get hubby signed up with the dental plan.
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