Debit Order deducted twice in one month

My debit order date is the first of every month. Russels debited my account on the 29th November and then again on the 12th December, stating that there was money in my account so the took the next months instalment as well.<br> <br> After numerous request re get my money refunded the same day as I had stuff to pay I had to go borrow money.<br> <br> On Monday the 14th December I again spoke to the customer care line explained the problem. Spoke the the manager \Grant"of customer care and he said he will do the refund"