Give back our money!

My husband phoned your Vehicle Finance department to get a settlement amount on the 12th of June 2018. He paid the full amount on the 15th of June 2018 and phoned your offices as we want the registration documents for the car. The 25th of June another installment was deducted from bank account, however the amount they refunded was not the full installment that was deducted. Please advise when can we expect the refund of the outstanding money. Also we would like a detailed statement as to how the settlement amount was calculated. We had a credit on this account for an amount of R4794.26 (credit received for a policy that we have cancelled). Was this amount deducted from the Settlement amount ? We have made so many calls to get this issue sorted out. At this stage we feel to move all our accounts to another bank, and not to make use of Absa Vehicle finance in future as it seems that they cannot sort out a simple query.