contract was cancelled, paid in full. still debit orders and harrasment over phone to pay cancelled contract

before contract was signed - simphiwe assured me that I can cancel the scholar contract November 2017. I cancelled the contract, pay the contract in full at tambotie branch. confirmed with the receptionist. since 7 November 2017 - debit orders is taken off - I need to refund it at my bank and keep minimum money in my account, as the stop order I signed doesn't work. planet fitness uses a different ref nr to deduct the money each time.. now they phone my son at university with outstanding money or account. what is on??????? please assist urgently. pf 551758