Double payment refund

I purchased a magazine subscription on 23 June via the vitality online shop. Upon my first attempt of purchase I used my credit card for payment and it went through after the OTP was confirmed. However, the merchant did not receive this payment and the screen confirmed that my purchase was unsuccessful. I then made an EFT payment to ensure I would get the magazine. The payment was then double as it went off both my credit card as well as my EFT purchase. I then proceeded to call the vitalityshop to notify them of this on 23 June 2015, and I spoke to Patricia ***. She advised me of the process to proceed with the refund. I then sent all the information to discovery, there have since been numerous back and forth emails and the refund has still not taken place. On Sunday it will be a month since this transaction occurred. It is a minimal amount but that is not the point. It could have been thousands and we would probably be the same situation. I have tried to resolve this too many times to mention and I would just like it sorted.