Edgars don't refund there customers if the customer make a mistake

My husband made a mistake and made an over payment on my account from his bank account He had to pay R 1800 but he paid R 7800 we now nee Edgars to refund us this R 6000 over payment but since the 3rd of December no response We did mail the proof of payment my bank account my husbands bank acc my ID his ID now they need a bank account showing both our names on it but we use separate bank accounts we nee to pay our other accounts and we nee to look after the kids who can help us with this case. If we phone them they say mail the document's if we mail what the want they need stuff that's impossible to get and now one can assist us at the branch. The edgars ref no is ********** 0926 GO we mailed to ********** , ********** , " ********** and ********** please assist us