That model is older and the batteries by now are not as good. I would run a battery test in Crosh.
https://www.howtogeek.com/309971/how-to-check-your-chromebooks-battery-health/
If the battery health is at 85% or below replace the battery. If the new battery doesn’t fix the issue than the issue is with the board.
I work for a school and we have several of these devices. Most are parts now and the ones out are stubborn to go to a smaller screen due to battery issues or they got lucky, and have a good device.