Are you experiencing problems with your iPhone 12, loosing mobile signal? Then you are not alone.
Thousands of iPhone 12 users are experiencing the same thing, and have written about it in various forums.
Here are links to some articles:
https://9to5mac.com/2020/12/01/iphone-12-dropping-service-unexpectedly/
https://www.tomsguide.com/news/iphone-12-has-a-serious-signal-problem-what-you-need-to-know
https://old.reddit.com/r/verizon/comments/jgyd82/iphone_12_pro_dropping_to_no_service_in_areas_of/
This has been going on for over a year at the time of writing, and there is still no fix for the problem.
You can try restarting, turning airplane mode on and off, reinstalling, resetting, etc., but the problem just comes back.
System update to latest iOS (15.1), reset/replace SIM card doesn’t help either.
In this article in the Apple Forum, a possible cause of the problem is described. That it lies with the 5G provider, and the method that the 5G band is assigned to the 5G client (iPhone 12).
The problem affects both 5G and 4G (LTE). So you can try turning off LTE so that you at least get 3G if it works. But, 3G is terribly slow, so it’s not a sustainable solution either.
If you search a bit, it turns out that the iPhone 13 is also affected by this error. So, if you are about to buy a new mobile phone, it is best to wait, or choose an earlier model without 5G. Or alternatively choose an Android mobile, also without 5G – as they may also be affected by the problem.
According to the article on Reddit, Verizon (telco in the US) should work with Apple on a solution. But, there are currently passed a year and no solution yet.
We are waiting in anticipation… But, as long as it is not known concretely what the problem is, it is difficult to predict a possible solution.
I will update this article if I discover a solution. Hopefully it will come in the form of a system update or the supplier updating their systems/mobile masts. If it turns out to be a hardware fault, it could be that Apple is making a recall, and it is necessary to send it for repair. If you find the problem solved before me, please send me an email.