TELKOM COMPLAINT

I am very dissatisfied and furious at the same time with Telkom. I've been a loyal customer for more than 8 years. I upgraded last month on one of my contract which expired about 2 months ago. I received my bill on the 4th of December and the amount I was billed shocked me R1700 for one phone. I did the upgrade via their call centre. I tried to call Telkom yesterday with no luck. This morning I tried and got through. The agent told me the upgrade still had 6 more months to go so I was billed for it and it was a open line. I've got 4 contract under my portfolio which are all top ups. When I did the upgrade i Mentioned it must be a top up. Telkom has been calling me sometimes up to 6 times a day to upgrade now they are charging me for 6 months as the the contract was not due for upgrade. I am sure the Agent who assisted me to upgrade did something that was not supposed to be done cause I would not upgrade if it was not due . My contact details ***. The number I upgraded *** . And now i was told i cannot change it to top up.