Club Factory — not ye received refund on cancellation of an order plus while a/c has been debited

My brother had ordered for jacket order no so67860588 but had returned the order has was about to get refund but instead of getting the refund his ac has been fully debited and to solve the query no one is picking call at customer care and we called at one of the no that person is telling us to download the app and give other a/c details and get refund immediately in my brother's a/c, i am not getting that it's club factory mistake that they debited my brother a/c so they should credit it back than why they asking for other ac details