Bf broke up with me and then txt me the next day.. why?

I txt him Sunday the he called me. We hadn’t talked since then.. then he txt me yesterday morning. I waited a few hours to reply. It wasn’t a messy break up I just didn’t agree with it. He said it’s because we have differences… like ok everyone no matter what has differences. Also there is an age gap w him being older. He said he still wanted to see me just nothing sexual and said we should take a step back, well I told him I’m not an option or something to fill his time. I won’t feel strung along either and that’s how that will make me feel. So I won’t be seeing him while he’s “indecisive”. But why would he message me? Then he hasn’t even replied or texted me this morning. I want to message him and say I won’t be doing the hot and cold texting bc I don’t text or contact any of my exes.