FNB won't help

My son is 16 he did a transaction for R25 on his debit card (most likely a ****) he is 16. An amount of 687.50 went of his account, I called the bank immediately and asked for it to be reversed the stoped the card emailed me forms and now I must communicate with this scanner to get his money back why can't they just reverse the transaction right away it is his right to stop a payment. But now we have to prove something while the real ********* get away with his money.