"no cell coverage" is draining my battery.

my battery has recently started draining very fast. in stings I looked at useage and there is a section called "no cell coverage" it is using at leasdt 60% of battery in 24hrs. yes I am in a poor cell area but that is not the problem as there are three identical phones in our home. they do not have this problem nor do they display this "feature". I have asked every apple user I know and nobody has this "no cell coverage" listed in battery settings. please can you tell me how to disable it or better still get rid of it. many thanks