I thought I had insomnia all my life, that is until I was diagnosed with ADHD at 28. When I started taking my medication for my ADHD that as a side effect normalized my sleeping, instead of 4+ hours of struggling to sleep for a hour or two before walking up again; I was able to fall asleep on a regular basis only after 20-30 minutes.
Some people just don’t have the right brain chemistry. I’ve been told a lot of remedies for sleeping by friends, family members and doctors. Keep looking if something isn’t working for you.