Pathetic customer service

When leaving France I was rudely told that I could not board the flight unless I paid for an additional 3 pieces of luggage which was incorrect. When trying to explain that it was an incorrect charge I was flippantly told to request a refund when back in SA. I have done so and it's now been over 7 weeks and still no refund. I queried after a month and was told to wait another 1-2 weeks! How long does it take to process a refund???