From what I can see, the device is from US, or at least running US (AT&T,Sprint,Verzion) software - this might be the reason.
I would suggest not to mess with the software on it as long as it works even if this is inconvenient - you can still disable/enable mobile data.
Hay I had the same issue with my note 5, after doing some research I found that it is caused by a switched off setting which is not accessible to users, And it can be overcome with a workaround which involves ADB. (Android Debug Bridge)
If you do not know anything about ADB follow this guide on restoring missing mobile data icon, which has step by step guide which anyone can follow, also include a much simpler solution, which might solve the issue.
Steps for solving the issue is as follows,