I got my Android phone flashed. A couple of buttons switched.
This led to my Wi-Fi Hotspot, USB and Bluetooth Tethering greyed and completely disabled. With these options unavailable, you won’t be able to share your Internet connection with other users.
My phone has been my modem for the past couple of years and I have successfully used it to grow my online business. It was some embarrassment that I suddenly was locked out. So while looking for the solution, I found out a lot of users were in the same pot of soup. So I’m sharing the exact steps I used to resolve the issue in minutes