Major upgrades have the potential to overwrite your current settings. Cellular data, for example, was enabled on your iPhone before the update but was immediately removed once it was installed. This is why you should wait until the update is fully loaded before checking your device settings for any changes. Try toggling Cellular Data off and on again as a solution in this scenario. Here's how to do it:
- From the Home screen, choose Settings.
- Cellular should be tapped.
- To turn off mobile data, press the switch next to Cellular Data, then hit it again to turn it back on.
After you've made these modifications, restart your iPhone SE to test whether cellular data is operating properly.
