Why would I be denied supplemental life insurance?

I was recently denied supplemental life insurance. My employer provides 2 times my salary if I die but I wanted to increase it because I have two kids.

Anyway, the insurance company came to my house, took my blood pressure, listened to my heart, took blood, urine, etc. I had ironically just had a physical exam one week prior with all the same stuff and was told I was perfectly healthy. I have always been a very healthy person and am only 32 years old!

Can anyone give me reasons why folks are denied supplemental insurance? Thanks!