LG G4 Discharging

[Koyoo]

Bought an LG G4 and charged it to 100%, never overcharged it at all because I literally just got it. But now when I put it on the charger, instead of charging my phone, it starts dying.

 

[B. Diddy]

Have you tried different charging cables/plugs? Is it plugged into a wall outlet or a computer USB port?