What is the most logical next event?

How to date someone you previously rejected
Find out if they're dating someone.
If the person you've got your eye on has already, you might need to let them go.
Ask mutual friends about their relationship status check social media for clues recall if you've seen them out with anybody
Assess why it didn't work before.
There was a reason (or reasons) why you rejected them in the first place. It can be easy to ignore these issues if you haven't seen them for a while, or if you're just feeling lonely.