Telkom is not stopping the cantracts as requested and keep charging me via debit order

I Cancelled my contract with telkom but telkom did not stop billing my account. I have been at the telkom office 4 times but it is still not fixed i am going to Cuba and on the 27 April 2018 and i am not comming back. I Would really like this debit orders to stop on my account. I have stopped it but it still is going off on my account. can i please get some assistance with the query as soon an possible before i am going away. My Case No is Ñ ********** 8