I’m not a hypnosis expert (yet) I’m afraid, so all I know is it works for some but others just aren’t ‘suggestible’ in the same way. It doesn’t work well for Diva but Snowflake doesn’t even need hypnosis to be unable to cum without my permission. People are just different.
Looks like it’s good old self control for you! But keep trying, maybe you just need to hear it more.