My galaxy s4 will keep losing service until I restart my phone and then it has full bars again. It will do this 3-4 times a day. Sometimes it will say I have service but my messages won't send and then half an hour later it will tell me I have no bars. I am running v. 4.4.2 and it says it is the latest version. I am getting frustrated as I am missing calls and texts. Does anyone have a solution?