iMessage and FaceTime still works but only via my emails and not my mobile number, because the freakin phone don’t know what my mobile number is.
I googled and tried every suggestion and nothing worked. Only managed to get myself worked up and frustrated.
I went to the outlet of my mobile carrier (DiGi) and I can see by the way the staff were passing my phone around that they were clueless.
They then assumed it was a hardware problem and suggested I go to an Apple Store/dealer, which I did immediately.
The Apple shop (Machines Sunway Pyramid) workers were just as clueless. After fiddling with the phone they came to the conclusion it has nothing to do with the phone and told me to just wait and hopefully things will get activated eventually.
If you’re going through the same I suggest you try what worked for me and hopefully it solves your issue like it did for me.
It is so simple. I went to my telco store (again), replaced the SIM card, popped it in and everything is working. Just like that.