iPhone X has no cellular network access since iOS 12 upgrade

Reading the troubleshooting steps you've already done, the next step is to try and install a fresh copy of your iOS, restoring your iPhone to factory settings, and, at the end, setting it up as new.

To perform this procedure, make a full backup of your device, then follow the steps here provided:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

When done, test your iPX connections capability (cellular data, wifi) for a while (without restoring any data).

If it's working fine, the restrore data from your previously made backup.

If the issue reappears, your data could be corrupted.

Regards

Giulio

First off, I'm not Apple, and I'm not blaming anyone else for anything. I'm just saying that the carrier controls your network, so they need to look at things. I've seen many times where updates to carrier files, which come from the network, and control what you can see in your network settings, and what your phone can access as far as the network is concerned, can cause issues with iOS updates. If you restore the device to factory, then set it up as new, not from a backup, test the network. If you still experience an issue, then contact your carrier. See what they have to say, and if they point a finger at Apple, then use the Contact Support link at the top of the page and work with Apple. A search of the forum will show many times where updates have changed the way users get networks. This was very apparent when many networks stopped supporting Edge and other 2G connections. Unfortunately for some users, their geographic locations did not support the carrier's faster 3G connections because of a lack of towers, but because the carrier had modified their carrier file, all users were affected. And if you are able to make phone calls and text, and you have cellular data turned on in Settings, then only the carrier can affect your ability to connect to data, not the iPhone.

Sorry about that, Zepher.

Well, if you used iTunes to restore your device to factory settings, then you set it up as new, without restoring your data, and you still have no signal, your device could have a hardware failure.

I suggest that you contact your most convenient Apple Store or Authorized Service Provider:

Apple - Find Locations - Location Selector

Regards

Giulio

See this support document for assistance, If you see No Service or Searching on your iPhone or iPad - Apple Support, and if that does not help, follow the last step after contacting your carrier to verify, and contact Apple Support if necessary.

This is not a hardware fault, the issue is with the upgraded software which has been more of a downgrade to be honest. I have the same issue since updating to the 12.0.1 operating system but the funny thing is if you have a 4G signal you will get mobile data but as soon as you only have a 3G signal the phone will just respond with no network connection. My phone works via the WIFI if i have a signal but if you don't live in a major city or your network has poor coverage with mainly 3G then you are stuck. Apple needs to fix this issue fast as i have bought phones and other equipment from them for years but i will be looking into if all the issues have been fixed before buying anything else.

John.

Hi Chris, that's not what the issue is here. The issue is that the update has stopped some phones from functioning as they should be. Mine has not had any mobile data network since the update and i have tried all of the above support you suggested. My 4G network works so the network is still healthy which allows me to use mobile data when i have it therefor it is not the problem.

ok so your saying that my network working prior to the software update but not after is just a coincidence? sorry not buying that.

the iphone is not recognizing that the 3G is a network connection for mobile internet. It will allow me to make calls and send texts but nothing else so i have a network connection.

lots of people are having the same issue with some resorting to reverting the IOS back through various methods but i don't see this as being the way forward, i think apple should be fixing the issues that they have created instead of blaming everyone else or ignoring it.

If you are seeing issues with 3G versus 4G, then the issue is with your carrier, not the iPhone. The ability to make network choices is up to the carrier, and carrier files are the ones that contain that information. That comes from the carrier, not from Apple. If your iPhone is changing carriers that often, then there would seem to be an issue with your carrier.