Find my iphone keeps turning off and back on randomly

My find my iphone app has something wrong because when i am in town it will randomly just stop sharing location even if i am in service. Then later on in the same night it will turn back on and this can happen a few times a night. I am not manually turning it off because i never go in it, it is just for my parents to see where i am at, but it will just stop sharing. I don't know what happens but it is not the first time and i dont know what to do?