I am being ****** ??? Breach of Contract by CellC

Had major issues with CellC late lastyear and my account was adjusted with 140 late November, this meant that since my account was in Credit, there would be no Debit in December I was informed that I will be credited with the remaining balance into my account. Quite rightly so in Dec no debit order went off for the 69 that I pay, however, come 27 January, I am debited 120, close to double what I am supposed to pay....WHY ??? No explanation from Cell C ??? I want to know why 120 was deducted and oh.....i am still waiting for someone to confirm if I was credited with R70 in December, Sent an email to enquire but I am now used to getting no response from CellC...