battery draining issue after installaiton of windows 11

I am having the same problem with my Surface Pro 6. It randomly shuts down while plugged in. This is very disturbing while you are teaching. After a restart the message battery 0% will show up. When the battery is at 15%+, I shut down my Surface, unplug, restart and plug the power cord again in, the battery is again at 100%. Sometimes I can work for days without any problems and out of the blue the problem is there again. I have uninstalled the battery drivers with no success. Besides the battery problem is there a heat problem when the Surface is plugged in.