2005 Suzuki Swift Suzuki Problem

I have a 2005 Suzuki Swift and just before Christmas, the clutch went. Rather than pay £600+ quoted at local garages (incl. Suzuki) I took it to the mechnics at the college where I work. Clutch has been replaced and although it feels a bit loose the main problem I have now is it won't go into reverse. I've told the mechanics at the college my problem but they say there is nothing they can do! Nightmare ... Can anyone please help ? Thanks, Debbie.