When I go to bed at night, I have to be really tired. I don't like the idea of trying to sleep and it's not happening. I turn on the radio, and a lot of people may say that it's not good to do that, but it helps me.
Technically, if you don't have a (diagnosed) issue with serotonine & melatonine there's not reason why you shouldn't fall asleep.
I do always find it helpful to not be too active later at night. Including with online activities, which usually means reading. That keeps the brain active.
As does the bright light of a monitor.
So I spend the last part of the evening only watching series/movies which allows my brain to slow down.
There's nice panflute meditation music to be found on YouTube. I always love that, use it as background when I'm recording meditations etc.
Maybe that's a good alternative to radio? There's one that lasts over 2 hours so ample time to fall asleep.