How to fix windows 8.1 lenovo laptop?

I just did a reinstall of windows 8.1 and now everytime it restarts it reinstalls windows 8.1 on start up. Why is this? Also my laptop gets a message saying drive not handled error has to restart but after this I re install windows 8.1 again and it is ok but when I turn it off and turn back on it starts to reinstall windows on start up. Do I need to buy a new laptop this one is only 2014 model.