upgrade

I am a telkom customer who is due for an upgrade, i went to the telkom store at Pavallion and the phone that i wanted to upgrade to was out of stock so they said that they will order it for me.I have been calling their manager but still no stock, i received my statement last week and to my suprise my bill came to an amount that i wasnt aware of and i called the call centre and they said that my contract is over so im being charged for the 5gbs now because my contract is over, i have upgraded in due time its not my fault that telkom has no stock of cellphones and you cant even follow up because there lines also do not work. This is absurd and i hate telkom right now im being charged R456.50 when i was paying R389 for my contract i want telkom to debit R389 because this is all not my fault plus no one advised me of this amount. It cant be that my package changes without any notification.<br> I would like to be contacted because at the moment i am really unhappy with telkom service.