Outstanding payment

On the 18 of Jan 2015 i used my card to pay R200 worth of diesel, the attended swiped my card twice, the sms came through on my phone but he received an error when it prints, he told me that the money didnt go through and i decided to keep the receipts as evidence so that I could be refunded, one transaction of R200 was refunded but the other hasnt, its been a month and a half, i talked to the manager(David) and he told me i need to provide my bank statement that he will submit to their bank as proof for the outstanding refund this is very bad service!! i will never use that petrol station ever again.