Disgusting service!

I have been a Cell C customer for at least 8 years now and I am severely disappointed in the current service (or non-service rather) that I have been experiencing, to date. Cell C has gone and renewed my contract with them and over and above this; have increased the rate - all of this WITHOUT my consent! I have been paying them an agreed installment amount on a monthly basis and have been in contact with them monthly up until 3 months ago where they seem to have dropped off the face of the planet. I have tried calling the Legal Department, but the calls never get answered (I have waited up to 50 minutes on one call), I have visited the head office in Port Elizabeth, but they were not able to assist me at all with my account either and I have sent numerous e-mails to customer service which have also been left unanswered. The only thing I was told at head office was that my account was handed over. Since then, I have heard nothing from Cell C and have received one call from the company that I was handed over to where I stated my complaint and they advised me to log a dispute which I duly did. However, I have yet to hear ANYTHING from either company! What more do I need to do here!? I WANT TO CANCEL MY CONTRACT WITH IMMEDIATE EFFECT AND I WANT SOMEBODY FROM THE LEGAL DEPARTMENT TO CONTACT ME TODAY!!!!!!!!!!!!