Product still faulty after multiple repairs

I sent an email via Acer's customer help service on their website three weeks ago (the same one I used to report the initial fault), but I still haven't received a reply so I'm posting my complaint on Hellopeter. I purchased an Acer Switch earlier this year, but have only been able to use it for about half the time I have owned it. After a couple of months the notebook would show that it did not detect the battery and it would randomly vibrate and go to the start menu. It was booked in with Partserve who had it for a few weeks and they replaced the motherboard. When I got it back, the Windows were not authenticated because it was embedded on the previous motherboard. The notebook went back in, Acer lost it for about a week or so, found it, sent it away to Acer. I got it back weeks and weeks later with an authenticated Windows, but it still says it does not detect the battery every few days, it still randomly vibrates and switches to the start menu and the display dims and brightens even though the auto- adjust to ambient light is de-activated. I emailed them three weeks ago to tell them that the problems persist, but have received no response.