Deposit

This property company is trying to ***** me, I sent them an email a month before moving stating that I will be using my deposit as my last months rent. This was due to the reviews I saw about them not paying out deposit. People have been waiting for their deposit as far back as 6 months. So they agreed only to now find out that I have been listed on TPN and when I call to find out how we can sort this issue out I have been sent from pillar to post by Sihle. I have sent them about 4 emails trying to sort this matter out but no one is responding. Please assist me what is the best way to deal with these people?