FNB refuses to assist us with unauthorized debit order

My son has an FNB account and there is an unauthorized debit order from an international company going off his account, he called FNB call center to have it stopped and they advised they cannot assist him and remove or stop this debit order. he then called back to close this account and was told that he must go into any branch to close the account, he goes to the Constantia Kloof FNB JHB and they said no they cant help he must go to Clearwater mall, he goes to clear water mall branch and they literally not full with like 4 people in the queue but tell him there is a 2 hour wait he must come back tomorrow and in the mean time this company is debiting his account for R18.50 a day, FNB and their staff is useless, *********** and to lazy to do their jobs. they making him run around and its absolutely disgusting i am with FNB for over 15 years and if they cant help us then i will also move away from them.