Resetting an iPhone with 'No Service' error A couple of days ago my iPhone 7 started to show 'No Service' error in the upper left corner of the screen. Tried several ways to fix this but nothing helps. While trying to reset it I got the error message:



title: iPhone Requires Service

body: You will not be able to set up this iPhone after erasing. A cellular update is required before it can be activated again.



What does this mean? Is it safe to proceed?
Don't reset. 
If you do, then you won't be able to activate your new iPhone. 
Some iPhone7 devices has this "No Service" problem. This is because it can't read your SIM. If you erase this iPhone, it will try to activate but since it can't read SIM you will loose your device.