Tivo Pace MG1

When I first signed up to Mediacom, I had the ability to watch tv on 4 Tivo devices(1 Tivo Pace + 3 tivo mini's). When I replace the Tivo box, now 3rd tivo mini can't find tivo dvr box. All I get is, "Tivo DVR not found" screen. I try resetting the tivo box and tivo mini, it didn't work. I wished I kept that first tivo box. I don't know what model it was. Maybe it was MG1 or XG1. :(