2 other ideas:
1. Have you tried a weighted blanket? I bought one this summer as I don't have a/c but find it hard to fall asleep without the feeling of a big blanket covering me. I found this one[0] from Bearaby which is wonderful. It's weaved together so doesn't provide much/any warmth. Just a lot of soothing weight.
2. This article - "How to Fall Asleep in 2 Minutes or Less" - helped me fall asleep quickly: https://www.artofmanliness.com/health-fitness/health/fall-as....