Airwrap repair customer service nightmare

Can anybody here help me. I first logged an issue with my Airwrap to Dyson back in January 25.  It was still under guarantee so they arranged a collection for 4th Feb to get repaired.  Great or so I thought.  Here we are middle of March, 5 failed collections later, countless emails, phone calls. Get the same response every time, " were so sorry this has happened, let me go ahead and schedule a new collection for you". I never get an answer as to why the collection has failed, I asked to speak to someone higher up in management, never happens. No one ever wants to speak to you, it's always e mail.  I am at my witts end and really don't know where to turn next.  I have put a post on Money Saving Expert forum and will do the same on Watchdog in the hope that they can provide assistance.   I  am furious with Dyson support especially when you consider the cost of this device.  I have asked for a replacement Airwrap to be sent and for compensation but neither have ve been acknowledged.  If  any one has advice it would be greatfully appreciated