Airtel — Airtel Mobile Number Detected Invalid By Facebook.

Address:

Jorhat, Assam

I am an airtel mobile customer with a valid registered phone number - [protected]. It works fine while calling people or sending SMS. But whenever I try to use this number to verify my Facebook/Google account an error occurs stating the number as invalid. I have taken care of all the proper procedure but nothing seems to help. I am really distraught by the problem. [Pictures attached]