If it shows unavailable, then your carrier did NOT enable it. No problems on my side after my carrier did actually enabled them weeks after everbody else in my family got them
OR it's just incompatible with my carrier
My device has a broken/dead wifi.
Up until kitkat i had no issues other than being unable to turn it on
In lollipop and later though i get a soft-reboot the moment i lock the screen or let the phone enter sleep mode.
After googling for months, ...