Bill Payment deducted twice

I paid UCT NBT via my FNB app Bill payment, the amount was deducted twice. I gave been talking to FNB to assist me with reversal or proof of payment for then two transactions without any success. Communication started in May, and this has not been resolved. Every time I speak to a new consultant, and they promise to escalate and call me back with feedback, still that does not happen. I am so exhausted and FNB doesn't care.