My LG flip phone hasn't had any service (no bars at all) in 5 days. I have turned it off and back on. I have removed the SIM card and battery. I am at home and have service here for the 2-and-a-half years that we have lived here. My bill is all paid up. I am not interested in upgrading to a smartphone. It does not have airplane mode. I am very frustrated. I need this phone for work. Please help me.