Phone wont recognize its on charge; Battery Drains Fast Even on Charge

[AC Question]

My s3 wont recognize that its plugged into the charger, sometimes once it has recognized its plugged up it flicks back and forth to plugged in then unplugged, the battery drains ridiculously fast, even while on charge it will lose battery.

 

[belodion]

Perhaps the USB lead is bad, or the USB port connector, among other possibilities.