[iMore Question]

Hi I just wanna ask that why my iPhone have no signal.
It never happens but yesterday there were no signal till now. Tell me what to do on this problem.

[Rob Phillips]

Welcome to iMore! Try resetting your network settings by going to Settings > General > Reset > Reset Network Settings. Then go so Settings > General > About, and see if a carrier update pops up. Keep in mind you'll have to re-enter your wifi passwords.
If that doesn't work contact T-Mobile.

[Arnold Copeland]

Maybe your dinamic is broken

[Rob Phillips]

Maybe your dinamic is broken

I'm no genius when it comes to iPhone internals but what's a dinamic?

[robertk328]

Maybe your dinamic is broken

I was thinking the flux-capacitor but could be wrong

@DevilishBanker suggestion about resetting the network settings should do the trick unless it's a T-Mobile problem. Because this can be a bit of a hassle to set up wifi passwords again, I'd maybe check with T-Mobile first to make sure there are no outages in your area. I'd then reboot the phone (if you haven't already). If those both fail, try the reset network settings.