logik a/c not working

im a little disappointed with game my husband bought a logic a/c December 2013. It worked very well for over a year. Then all of a sudden the unit wont stay on when using the aircon. when u swt it to aircon mode it works for about 5min then automatically switchs its self off for 3secs and then restarts. It does this non stop ive made sure the filter is clean and pipe isn't bent but it still does it. I phoned around to find someone to repair it cos i sont have the slip and everyone says u cant get parts for it because its made for game stores only. So i phoned customer care and the man said to me without slip i cant send technician. I dont mind paying to have it fixed but hell where do i get parts