Refund of R3500

I join credit rescue two months back. In June they deducted double from my account an amount of R7000, R3500 is my payment, the other R3500 was taken as if I bought something. They debited twice . I sent my complain on which I was promised it will be settled in 72 hours. Today is almost three weeks. I have submitted my bank statement hoping it will be refunded until now nothing. Please I need my refund as soon as possible I don't know which branch debited the other money, but it was debited on the 22 of June.