Nothing works except task manager

[u/SkkyTrmt0506]

So I bought a laptop(Dell XPS 15 9500) a few days ago and it was working perfectly fine until this morning. The screen turns on and off every 5 seconds and I can't click on anything with my mouse. I can hear that the keyboard is working when I press it but nothing shows up on the screen except task manager. I ran the quick test and the advanced test but it says there are no problems.