Failed Refund!

I purchased items online from Makro begining of April - goods were collected from Courier, as wrong items were delivered. Waiting for refund - to date nothing. Cant get through on their telephone number either. Never again will I do an online order. Get an email from them, saying that "Failed refund" - this is to my credit card. How does is a refund "Failed". Absolutely useless service that I have received from them.