Vodacom refund for and incorrect billing

In July 2018 I decided to cancel one of my 2 cell phone numbers I had with Vodacom. This process should be pretty straightforward right. After sending a mail to ********** requesting for my 1 cell number to be canceled and the 2nd one to be changed to a different contract I got the surprise of my life at the end of the month when not only did they not cancel my one sim card as per my request, but changed both numbers to a new contract each costing R499 pm. Now I'm a reasonable person and know that people can make mistakes or maybe the person handling my query did not understand my request so off I went to Vodaworld to speak to a consultant directly. The consultant a Vodaworld handled my query( and frustration) with a calm manner and got my one sim cancelled. I requested that the incorrect charge of R499.00 be refunded in the form of a credit on my monthly account. After spending nearly 2 hours at Vodaworld I left with the assurance that I will receive a refund at the end of the month which would have been end September. Beginning of October I noticed on my monthly bill that I did not receive the refund I then decided standing in a queue at Vodaworld for 2 hours is not worth it i therefor decided to phone rather. I asked to speak to a manager and was assured that the gentlemen is spoke to was a manager and that he could sort my little problem out. After what could have been an half hour and plenty reassurances the gentleman said he will take care of the refund and will phone me within 5 days to confirm that the refund has been passed. Needless to say the gentleman did not phone me to confirm that the refund has been passed and therefore my end of October bill was the full amount and not the amount less refund. I am out of contract with Vodacom and will port my number to one of the other cell companies, it's sad that after 20 odd years of being a loyal customer it has to come to this.