For what it’s worth, I tried CBT-I and it wasn’t successful for me, then tried ACT for insomnia which solved the issue. Specifically via a book called “The Sleep Book” by Guy Meadows. Highly recommended.
Thanks for sharing—can I ask in what form you tried CBT-i? (e.g. with an in-person therapist, online course, book etc).
Have run into ACT for insomnia in an article or two, but haven’t met anyone like you who’s used it. Have downloaded the book and will give it a read!
Tried in an online course. Hope the book helps