Cancellations department *****s money Vodacom

I contacted Vodacom on the 07/09/2017 to cancel my contract, they sent through the cancellation quotation on the 07/09/2017, I made the full payment and e-mailed the quotation signed, proof of payment and copy of my ID on the 08/09/2017 to retentions.cancellations@vodacom .co.za, I then sent the same e-mail again on the 11/09/2017. I have now been handed over to their legal department as Vodacom apparently never put the cancellation through, Vodacom has asked me a year later to call the legal department, I have tried on numerous occasions to get through to them and they never answer their phones. So Vodacom has given me a bad credit record for not putting through my cancellation and informing me that I owe them when I clearly do not owe anything, so what has happened to the money I paid for the cancellation over a year ago? No one at Vodacom can apparently assist me on this issue, and my name is being dragged through the mud due to their incompetence, this is unacceptable and I want this resolved a.s.a.p.