billing

im getting emails and calls from Vodacom handing me over for an account that they never deducted each month............ive given them instructions since the day I took out the contract to deduct n yet they didn't deduct.......they billed me for data usage which was not even mine and ive told them to deduct each month for my contract and still they did not now they billing me for outstanding payments I am not paying as it is not my problem they were giving instructions over n over and yet didn't do so

I want someone to call me so I can cancel this contract ive been having problems since day one