Bad Customer Service

My son has a youth account with FNB which is linked to my account. He had singed up for Itunes and we were paying monthly subscription for that. However on the 08/09/2019 the Itunes subscription was cancelled and the account appear as expired. Itunes made attempts to debit the account regardless on the cancellation, this lead to me being charged for insufficient funds in the account I paid R178.00 in October for these bounced debit orders. I called FNB and they suggested that I cancel the old card and request a new one which I did. This to me meant that the account will no longer be accessible and the bank charges would stop if things were done correctly on the system.The new card was delivered on the 2nd of October 2019. To my surprise the account is on minus again because of a debit order that I thought we have dealt with. On the 01/11/2019 I called FNB with the same query and again I was told to cancel the card and that was done. 06/11/2019 I called to query this amount that needs to be paid by me in bank charges which are not even supposed to be there and no one could give me a proper answer instead I was transferred from one department to the other. I spent over 20 minutes on the phone and still no solution. So now i'm supposed to pay for a replacement card and bank charges, this is just too much exploitation.