Lenovo Laptop Charging Problem?

I have a Lenovo G50 - 70 Laptop. Running Microsoft Windows 8.1
From Yesterday, When its plugged in while the Laptop is on, it says charging but the charge percentage never goes up nor go down, it remains constant. (The Battery charge indicator blink once every 5 seconds interval)(The battery charging animation in taskbar also stops, charging is still written though).
When i turn off the Laptop the battery charged up without any problem.
What could be the problem. I've search on google but couldn't find the answers.
If anyone encounter this problem and has a solution for it,
can you kindly share it.