Why aren't you sleeping exactly, is it just that you're sleep procrastinating or just laying in bed and not able to shut off?
For the latter; make sure your sleep schedule is correct, if it is currently out of whack; fix it, how? wake up at a consistent time always and use sleep aids if need be, get good exercise/activity during the day, make sure you're getting all the vitamins and minerals you need from food, supplements can also help in sleep, I've found success with 5HTP, green tea, L theanine, CBD oil, and Montmorency cherry and set a good sleep enviroment; make sure you're not too hot and that your room is as dark as possible.
the sleep aids i mentioned could be something such as kalms which you can get online or in stores but I must advise you to only take it to help fix your sleep schedule if you need to sleep early, avoid using it consecutively as this will make your body become resistant
If its procastination problems I'm not sure how to fix that, best bet would be to move distraction devices to a seperate room so you dont distract yourself when trying to sleep.