My husbadn was hurt bad in a car accident what do we do?

my husband was on his way home from work and an on coming car was over on his side of the road my husband went off the road hit trees and was hsopitilized for 14 days almost amputation on his leg thta has been rebuilt, we have bodily injury collision comprehensive fully insured why is the insurance saying thye will only pay the medical part for 5000 dollars what do we do?