Bad start to our new year Thanks Cell C

Every month our accounts amount goes up This month they cut our phones off because of late payment and only put it back on on the 16th now they deducted R1400 and we didnt even use our phones for half of the month We don't get statements at the end of the month to show where the money is going to or why our account is so high Our account started at R700 and went up up until now for R1400 My husband is ready to cancel the contracts but they said if we cancel we have to pay in like R6000