Worst service ever!!!

Good day.<br> <br> I received a phone call from Telkom to ask me if Telkom could upgrade my 4mbs line to a 10mbs line. I agreed to this arrangement because the sales assistant said it would be at no extra cost, it was a promotion, I would be contacted to confirm the change of the contract to a faster line at the end of the month. The installation was fast, the two gentleman was polite and very professional, both of them confirmed that the upgrade was at no extra cost. <br> <br> When my bill came I was charged for a 10 mbps line and the 'Promotional' installation and Telkom decided to shape my line. I agreed to an unshapped uncapped line from Telkom. I'm getting very frustrated about this situation. Telkom cannot go about changing agreements and the properties of the line. They haven't asked for any written consent to agree to any changes on my contract.