Phone is not charging

When I have plugged into the socket of the electricity line, than connect the charger to the phone's charging port, than a red light is beeping near the phone's charging port. And the device won't be able to start without pressing the power and volume button together. Whether If it is start for connecting with the charger, the battery status of the phone is not charging, which is declared in the "about phone" option. But the signal of the top of the display is charging... please solve the problem ASAP