E5-575-54E8 not charging even though charging light on

My E5-575-54E8 doesn't charge the non removable battery even though the charging lights comes on and the display shows it's charging. After some minutes, windows 10 informs me that battery's running low and that I should plug in the charger, but it's already plugged so I unplug and plug it back again and the battery continues to drain until it dies off, and won't even stay on even though it's plugged in until after a while. I got a new charger and same problem. Then, without any notice, it starts charging again normally and it works fine for a week or so, but then it does it again. It seems like if I let it sit for more then a day unused, I get that charging problem. Any ideas? Thanks