I suffer with insomnia, so I can empathise! It’s a struggle.
Have you heard of sleep hygiene? It’s about routine, going to bed and waking up at the same time, no matter what. Bed is strictly for sleeping and not watching TV etc. No caffeine, alcohol or smoking before bed. I am also prescribed zopiclone but promethazine (you can get over the counter at a pharmacy) is helpful for some people. It is only meant to be used occasionally though.

If it continues, do speak to your GP.
Hope this helps!