Bad service

I moved into a town house in 2013 managed by Angela a useless agent that never attended to anything. January 2015 Gerda phones to say I must sign a new lease for the escalation. At the office they slipped up and made it my problem. I was told to pay the escalation plus admin. GERDA came with the owner of the unit who was on vacation from Dubai, I signed the lease for 6 months in the owners presence. I asked for my copy to be emailed to me. It never happened. I also asked Gerda and Angela to advertise the unit as we are relocating. I had no response from any1. After moving out end of May 2015. I phoned and emailed Lynette numerous times and she never return calls. Finally she emails me after a month stating no deposit due she has given the owner the deposit. Yet my deposit was kept in a trust account. So what has happened to my deposit including the interest for 2yrs. I have all my backup emails. I never signed a lease for 2016 at all. No response from Angela or Gerda, the receptionist knows how I used to phone all the time and they never available. Their service stinks I would never again rent from Experia. All I want is my deposit with interest thanks