When you caught your swarm, did you leave your box near where the swarm collected it, or did you move it back next to its previous locations? When you caught it, did you leave it there by the swarm spot, or move it immediately?
I have found that my own swarms tend not to stay (they re-swarm), but swarms caught elsewhere always have thus far. Another idea is to leave the box by the swarm spot for a couple of days.
Last year we only received two or three swarm calls. We have already received seven this year, all in the last 10 days.