If you search the CH Shop for the word sleep, you'll see quite a lot of things to help with sleep.
I hadn't seen this one before but it looks interesting...
https://shop.creepyhollows.com/hypnokinesis.html
A Sandman spirit may help too.
But...based on my experience, just as with all magic and work with spirits, it helps to maintain realistic expectations. As I have read CH say, neither magic nor spirits can make our lives perfect but they can really help - if we're able to work well with them.
When it comes to sleep we'd probably do well to take note of modern sleep scientists' advice on what they now call sleep hygiene. One key thing they say is to not stay in bed awake for long periods. It helps to get out of bed, do something else then go back when tired. Our mind-body system needs to associate be with sleep, not insomnia.
tl/dr: I think our minds play a big role in sleeplessness, as in almost anything, including magic and spirit work. Even if we have some really good spells and spirits for sleep, I think we must not neglect the contribution we make ourselves to sleeplessness...or to sleeping well.