G. K. Publications — activate my cd key

The CD which i had receive along with gate 2015 electrical engineering book is not supporting.i already entered correct key given on CD then also it shows activation key is invalid.
My name is Shubham Thakur and contact number is [protected]
my cd activation code is [protected]
emaid id- [protected]@gmail.com

The CD which i had receive along with cmat book is not supporting.i already entered correct key given on CD then also it shows activation key is invalid.
My name is jay patel and contact number is [protected].
my cd activation code is [protected].
my mail id is - [protected]@gmail.com

hai,
my cd asking mobile verification how did i do that??????????????
my code [protected] 2016 gate book

Hi I had Mechanical Engineering CD 2015 I INSTALLED IN MY LAPTOP IT'S SAYS INVALID KEY TELL ME HOW TO ACTIVATE THE CD