Do I have a chance?

So there’s this guy I like. We used to work together before I moved jobs. I don’t have his number, I don’t have his Snapchat or anything. I do see him on dating apps and he does come up as a friend suggestion on Facebook. So I’ve seen him at least once a month on the dating apps. Do I try and add him on Facebook or wait to see if he comes across on my dating apps again and then compliment? I did ask him out but at that time he said he was talking to someone and again since then I’ve seen him several times on the apps. Do I have a chance and what do I do?
Do I have a chance?
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