1. Re-Insert your Tesix Sim


One of the first things you should try is removing and reinserting your Sim card. While it’s unlikely that the card got dirty or dusty while in your phone, reinserting forces your phone to re-read the card, and can jolt your cellular data back to life.

The order you should do this in is:

  • Power off your iPhone
  • Remove the SIM card
  • Re-insert the SIM card
  • Power your phone back on

 

2. Turn your roaming on and off


It may sound counterintuitive, but a lot of people who experienced iPhone data outage have found this to be a reliable solution. Specifically, after certain iOS updates, some devices have been affected by a bug which caused the OS to get confused about when you’re roaming.

If you think you have this bug, go to:

  •  Settings
  • Mobile Data
  • Mobile Data Options
  • then switch on “Data Roaming” and reboot your device.

 

3. Reset network settings


If cellular data stubbornly refuses to cooperate, we may need to reset the network settings completely. This will wipe out any saved Wi-Fi networks while resetting your cellular data settings to their defaults. This means resetting your network settings can also fix Wi-Fi problems, if you’re having any of those.

  • Opening Setting
  • Scroll to General
  • Scroll to Reset
  • Tap "Reset Network Settings"

 

4. Factory Reset


Optionally, you could leave the phone in its “like new” state, which might have removed an app or service that was messing up your cellular data. If you want to do that, make a backup anyway: you might regret it if you don’t.

  • Opening Setting
  • Scroll to General
  • Scroll to Reset
  • Tap "Erase All Content and Settings"

 

If the cellular data isn’t working on your iPhone, you can use the above options to fix it. They’re fairly general, but they’ll work in nearly any case. Of course, if you have hardware problems, software solutions won’t fix it. In that case you’ll need to get the device replaced.