Company's negligence

My mother has had cover for her kids since I was born, now my brother has passed on & he's 31 years old, they been debiting her since & up to date now they telling her she's got no cover since she didn't take a separate cover/policy upon him turning 21 years yet they been debitimg. Now who's fault is it as underwriting comes from their side & they should inform & update client's cover accordingly. What is a policy renewal for or should I also bring my brother's body to their offices for them to pay out. We supposed to bury him this Saturday & they giving us this ****. They should cover as promised he's unemployed & dependent on my mother. It's never been brought to my mother's attention now when they are supposed to pay out they giving us stories.