VODACOM ARE THE WORST EVER

I HAVE HAD IT WITH VODACOM, I HAVE HAD A PROBLEM WITH THEM DEBITING MY ACCOUNT, SO I CALLED THEM TO SOLVE IT, KEEP IN MIND THAT I HAD THE FUNDS IN MY ACCOUNT FOR THE DEBIT TO GO OFF. VODACOM DOES NOT TAKE THE AMOUNT I AGREED ON, THEN THEY STILL SEND ME A SMS SAYING I HAVE AN OUTSTANDING BALANCE, I CALLED THEM TO SORT IT OUT SENT THEM MY BANK STATEMENT AS REQUESTED BY THEM, THIS IS TWO MONTHS AGO AND STILL I HAVE NOT HEARD BACK FROM THEM , MY DEBIT GOES OFF AGAIN WITH THE ADDED FEES WHICH THEY WERE TO SORT OUT AND I AM AT THE END OFF THE ROAD...THEY PROMISED TO GET BACK TO ME IN THE NEXT SEVEN WORKING DAYS AND STILL NOTHING...I JUST WISH TO CANCEL THIS CONTRACT WITH THEM, AND LET EVERYONE KNOW WHAT PATHETIC SERVICE THEY HAVE...THIS IS TERRIBLE! I STILL HAVE NOT HEARD FROM THEM, I HAVE BEEN TO THE STORE WHICH NO COULD HELP ME, I CALLED TO SORT OUT MY ACCOUNT AGAIN AND STILL THE GUY WAS SO RUDE, BASICALLY VODACOM IS MESSING UP MY CREDIT HISTORY AND THIS IS MAKING ME VERY ANGRY BESIDES THE SERVICE.