Hi, please read patiently but the ending will surprised you. I had an old iPad Pro 11 Inch Sec Generation with cellular data model bought from Apple Singapore but using in Malaysia. An active sim card was inserted in the iPad and everything was working fine until one day I turn on my device from battery drain out showing "Your iPad cannot access mobile data until it has been updated". So I try updated my iPad to latest iPad OS 16.1.1 on the device itself using wifi network but was stuck in "verifying update" even trying so many methods searching online for example: insert sim card/remove sim card or sim card tray. And finally with good luck this time I manage updated my iPad to latest iPadOS 16.1.1 by connecting to iTunes on pc and it worked successfully.
But bad luck also, even updated to latest iPad OS the error message "Your iPad cannot access mobile data until it has been updated" still existed and I still cannot using my cellular data on my iPad. I had also try checking is there any carrier update setting appear on Setting>General>About, but no.
Most important is that this problem is not new to me, I had experience same problem last few months ago. At first, I contact Machine store for help but they have no idea on it and too bad my warranty is out I cant replace a new one, that is the solution from Machine/Apple. Also checking from my carrier service, no problem with my sim card and my billing part as well. So I blindly try luck on third party repair shop, but still the same they have no solution on it some mentioned is software bug/some told me is hardware problem. Had try restore iPad/erase device all did not work and eventually caused my device cannot activate totally die. I was so upset and give up after all the effort put. It happened when my device only aged 1 year+ from purchased date.
Here come the interesting and weird part, after put my "Die iPad" aside for few weeks to a month, cant remember clearly. One day just testing luck without much hope, I connect again my iPad to iTunes on pc to run restore and update, surprisingly this time the whole process go through smoothly, my iPad can be activate back (previously failed on activate device process) and reset to the new one with cellular data working back as normal. What the heck..I remember the whole drama happened when still on IOS 15 time, and after few months the same problem came again. Both time begin with cellular data access failed, request to update. I really not sure what is the problem or relating to new IOS or just software bug. Apple please fix it, it a continuous problem, please help.
