Not refunding airtime

I went to buy airtime at the Vodacom 4u store at liberty mall and it was put into the wrong number so I went back to the store the same day and queried this so the lady told me they have to send paper work through to the head office and it will take 24 to 48 hours to be refunded and it's been now almost a month and still nothing has been done and no one has even given me a call to let me know what's going on.