Hi ModestRose,
You mentioned in your first introduction of the issue that you both agreed to him being your slave. I was wondering how intense your BDSM relationship was prior to this agreement because maybe the jump to 24/7 if you only played lightly is too much at once?
Perhaps starting with two rules a day would alleviate some of the rebellion he's feeling? Maybe a rule that focused on you first thing in the morning and one for the end of the evening would help to integrate getting used to 24/7 for his mind set. For instance, preparing the coffee, or serving you breakfast/dinner, perhaps a nice foot massage (or any other fun kinds of massages

) to end the day right. If his attentions begin and end as focusing on your needs and pleasures, maybe that would help to build towards 24/7 if that is still the desire. It's also starting slowly with only a couple rules a day which may help him to not feel so "managed" too quickly.
Unfortunately though, like Ruby mentioned, if his heart is not fully into 24/7, you're not going to be able to make him do it, nor would you probably want that for him. 24/7 takes a strong desire and commitment that doesn't just occur right away sometimes from my understanding.
It's good that you've been being consistent because that is definitely an important aspect. I'm sorry you're both having a tough time working through this, and best of luck to you both.
~orchidsoul