Chosen Solution
Hello, This problem has only recently came up my phone keeps loosing signal and is saying ’ No Service’ but when I go on flight mode and come off I have 3G which doesn’t make sense because 5 mins later it goes back to No service, I have tried turning my phone off but its the same as flight mode it only lasts for a few minutes.
Try reseting network settings, if that wont do you have bad antenna or baseband chip, try opening your phone and reconnecting your jacks. If nothing helps, you need the repair and send it to nearest iPhone service to have your parts changed.
