Can't put my computer to sleep, and it won't shut down

1 month ago, my computer started not working properly. The sleep function AND simply to shutdown the computer startet not working anymore. Have searched for an answer in several weeks now, but without finding the solution. When i try to put it to sleep or shut down the computer, the screen goes black but the computer is still working. It's like it wakes up again, but the only way to use my computer again, is to hold the on/off buttom until i shutdowns. Then i can turn it back on and use it again.

I've tried looking through my drivers to see if any of my drivers woke my computer up when it goes to sleep or i try to turn it off, but it haven't solved my problem. I've also tried to update everything i could and again haven't found a solution.

Hope someone can help me solve this problem, as it is very irritating and not good for the computer to get turned off in the way im forced to do, pls help.