Life Insurance - denial of Spouse Life coverage I'd been paying for years, due to "an approved Waiver of Premium" ??

My husband and I both work for the same company, and were married in 1999. In 2007, I began paying premiums for Spouse Life insurance through my company.

My husband has been out on medical disability for several years, and just suddenly passed away in May.

In finally getting around to submitting insurance paperwork, etc., I was told a couple of weeks ago by my work's insurance company that since Kevin was out on "an approved waiver of premium", I was not eligible to elect Spouse Life. Therefore, they sent me a check reimbursing me for the premiums I had paid since 2007 (without interest, I might add).

Can this be correct? and legal? Had the human resources department of my company known, and told me I wasn't eligible for this coverage, I would have likely pursued other similar coverage outside of work. How can they just tell me after almost 4 years of paying for this coverage, that I can't have it?!

Thanks so much for any help.