Vehicle Contract Disagreement

I recently purchased a new vehicle and Standard Bank financed the vehicle (thank you so much). When I bought the vehicle I specified that I would be taking delivery of the vehicle on the 7th of August and confirmed with the dealership that the first payment will be deducted on the 26th of September 2015. The first payment went off on the 26th of August. I called Standard Bank and ask that the money be refunded, they logged a query and I was told someone will call me back. I have now made about 7 calls to Standard Bank and no one calls me back. I have been told that on the contract they have the first payment will go off on the 26th of August however on the mandate and payment instruction I have it states the 26th of September. <br> <br> This has been going on since the 27th of August and clearly no one can assist me with regard to this. I need to speak to someone you can actually assist with this query.