Interpreting results for lab report- HELP

My lab report is about the relationship between sleep quality and self control and additionally the effects of circadian preference (Wether you prefer morning or evening ) and from our results we found that :

found a negative correlation between the quality of sleep and self control for all participants and evening participants and no relationship for morning types.

what does this mean can somebody please help what I could interpret from this.

Are you confused about what the results show? In other words you found that circadian preference MODERATES the correlation between self-control and quality of sleep. Moderators are variables that alter the relationship between two other variables. People who are evening types show a correlation between self-control & sleep quality, and people who are morning types show a smaller (or non-existant? you havent mentioned this) relationship between self-control and qual of sleep.

You can go on to explain the reasons why this may be the case, don't really know why myself. I'd take a guess that morning types naturally have a sleep pattern which matches social norms (e.g. for starting work at 9am), so they can get to bed early and wake up early with little effort. In contrast, evening types would naturally wake up at 10am, so they need effort to be able to discipline themselves to go to bed early so they don't end up going to bed at 3am and waking up at 7am to get to work the next day. I'd assume that in this case having good self-control would allow the evening types to discpline themselves into going to bed a little earlier.

thank you for your reply, Yes you are correct no relationship was found between the sleep quality and self control in the morning types? but a relationship was found in the evening types, this is what I'm confused about.