Well it could be that your battery is dead
It could be that your AC Adapter is dead
It could be that the charging circuit which is on your motherboard is defected.
We will need more information to try to help you out with this.
Can you eliminate any of the above? for us
G752VY-DH72 Win 10 Pro
512 GB M.2 Samsung 960 Pro
1 TB Samsung 850 pro 2.5 format
980m GTX 4 GB
32GB DDR 4 Standard RAM
Z97 PRO WiFi I7 4790K
Windows 10 Pro
Z97 -A
Windows 10 Pro