When I go beyond 1 minute and 30 seconds, I always exit out of arena, go to group base, run a bit, go back to Konoha, run a bit and then go back to Arena, click on Rank Battle and boom! Finds an opponent immediately. Works for me anyways. Sometimes, I also refresh my browser or the mini client and then I can immediately find opponents.

Why wait that long when you can just exit after a minute of finding an opponent and then re-enter.