Contradicting cancellation cost

I made enquiries regarding cancellation of contract due to not getting any joy from CellC where people are not able to get hold of me on my number *** as I would like to port my number back to Vodacom since I never had any problems with them. My unused airtime does not roll over anymore also and I'm the loser. I even did a SIM swap (which cost R99) as suggested but still no joy and I spoke to couple of people with CellC and they complain about the same problem. I was informed the settlement amount is R4195 according to my calculations and according to the complaint that CellC logged with Consumer protection where CellC is buying over peoples contracts they are saying that the other operators is overcharging the people because only the cost of the handset must be recovered plus usage of outstanding bill and that is how CellC does it according to my calculations the amount owed to CellC should be (160x19)=R3040 (my account is capped so no outstanding usage) why is the amount due for cancellation more than R1000 more so CellC is contradicting the complaints they make against other operators. Please provide me with a detailed breakdown of how the cancellation cost was obtained.