Chuwi Herobook Pro 14.1 Intel N4000 Battery Problem

I’ve got a problem with my CHUWI Herobook Pro and I don’t know how to fix it, like the battery shows 100% but as soon as I unplug it, it just powers off after I put the cord back in and get into windows it says that I have 0% left. Any fixes or do I need to repair the battery? Also I’ve had this problem since I bought it. Yes I’ve been inside the laptop to check the battery connection and it WAS plugged