Hey Ravi,
Thanks for you attention and suggestion. I did try to do your suggestion, but sadly, as I mentioned before, all the efforts was futile. I can't get back my bluetooth icon. But again, today, 3 days after I post this, the bluetooth icon came back and I expect it to be missing again at some random time.
So I guess, this issue isn't done for me, or at least until I can assure it in the upcoming days. I'll update this issue when it come up again.
Thanks for the help anyway, have a pleasant day. Cheers!
The suggested method/s doesn't work for me too.