Debited R459 Twice Still not REFUNDED

I bought an item from Zara online on the 9th Online the payment went threw same day on the 18th again they took from my bank account the same amount of money which means I was charged twice for one item I’ve been trying to get assistance from live chat but still they just giving me a ran around I forwarded everything they asked for on live chat my bank statement but still they keep apologizing This is ridiculous All my bank wants is a written email as proof stating that Zara has acknowledged that they charged me twice so my bank can reverse the funds back to my bank account