When plug in the light does not come on to charge it. What is wrong with it ?

Most shavers will have little metal conductors on the bottom back that when placed into the charger device must line up with the base charger. Try re-adjusting your shaver in the base.
If your shaver does not use a base-charger, and simply plugs into the wall to charge, a lot of cheaper models have low quality cords etc that can be easily damaged. Sometimes people like to rip of the charge-cord out of the shaver socket without realizing theres a mechanism to properly disengage it and thus cause damage to it.

Hope this helps

-Jord