Get professional expert help from these folks:
https://centreforsleep.com/
They saved my life.
They will diagnose you, provide therapy and prescribe the right medication safely. And they will teach you about sleep hygiene and how to safely use things like Melatonin. Don't expect your family doctor can help with this. They aren't equipped. Get help from the expert professionals
PM me if you want to know more. Happy to share my experience.