Pathetic Customer service on a deal that has been incorrectly concluded!

I received a call about a month ago from Mondo offering me a contracted deal with Telkom. I took up the offer on condition that my current line with Telkom be upgraded (as it was due for an upgrade) . I received my new line only to find out that it was added as an additional contract! I immediately contacted Telkom and was advised to contact Mondo . i have sent through numerous emails , one of which i was assured that the upgrade was conducted successfully however this is not the case as per Telkom's records. additional emails were sent to rectify this as soon as it was brought to my attention of which no response or solution has been received... I am not sure who exactly is responsible for this mishap however i am highly irate at the level of customer service i am receiving . this is exactly the reason for my initial hesitation to take up deals over the phone. Please rectify this ASAP since sadly i will be liable for the debit of which i refuse to pay due to the negligence on your side as i specified it needs to be an upgraded and was assured that it was done!