Double deduction for payment arrangement

I have a payment arrangement with Nedbank for my loan. My account got deducted twice this month. Once on the 30 Nov 2019 and again on 13 Dec 2019 without notification. Every other month the payment arrangements go off without a problem. Can the additional deduction for 13 Dec 2019 please be reversed. I tried getting through to the Call Centre but the call queue is always long.