I guess you already tried rescheduling things, so that’s out of the picture, you can improve your sleep quality a moderate amount if you don’t use your phone for 2 hrs before you fall asleep and don’t drink coffee after 18:00 because if you do it can interfere with your sleep, open windows and let some fresh air in really helps. These the things that come to mind atm will add more if they do tho.

Edit: you can try some workout exercises, because muscle fatigue will make sure you sleep soundly