I did a thing...

I started talking to my ex. I know. It's not recommended. Anyways I want to be friends ... maybe have sex lol FWB. I'm confused as to what to do. I know I should leave him alone but I don't want to ... That sounds bad. But im a very open person and I say what's on my mind. I told him we should hang out I'd cook for him and we'd have drinks and chill. He agreed. I saw him casually nothing sexual a few times prior to that...but then he had a situation with his daughter and we cancelled. I let it go at first but I was really pissed because I planned it out perfectly our schedules were not matching up but this one night would've been great. So I went off. He apologized for cancelling the next day but I was still mad. Like how do I fix it...I know what y'all gone say leave him alone...but ugh it's hard. Do I apologise (I kinda did) but now he's ignoring me...our relationship prior to all this lasted about 2 years. This year I've distanced myself from him but I guess he was in his feelings when I did that but I never intended to hurt him. And it seems the tables have turned I guess...any advice?