Shocking service

I have a Bond with Standard Bank. Last year sometimes they changed my monthly instalments to R1 800 instead of R7 200. I noticed the problem after three months and contacted them. They acknowledged that there was a system's error from their side and then updated the profile. I then requested them to reduce the bond' monthly installments and they told me that they have decreased the instalments to R6 200. They also told me that they have extended my contract to 30 years and promised that I will receive new contract documents and to date I haven't received any documents (new contract). I stopped paying the bond from September 2014 and they have now handed me over to their attorneys. The problem why I have stopped paying is because I am still awaiting for the new contract as promised, so why am I now handed over to the attorneys. I was also not contacted about this issue. Could someone please contact me urgently so that we can make the necessary arrangements as I don't want to lose my property?