********** activities on gaming purchases

My son has a XBox One and every time he makes an online purchase they hack his account and ********** purchases goes off for the exact same amount every 2 days. First we used our credit card and the stole about R9000 in transactions. We reported to the bank and still nothing. We then put a small amount of money on my son's card and now every time we put money into this card they take it. We now had to stop this card as well. It is not safe to purchase through Microsoft the site is not secure!! A friend of his lost over R20000 on this ****!! Microsoft will have to look into this asap!!