New Contract deposit not agreed prior

Good day,<br> <br> I have app**** for a new contract with Telkom mobile through one of the contractors known as Bluetechretail. They came through to my house on the 5 of May to do a demo and I app**** for one of the packages on promotion. I have been following since then and I have been told all sort of stories. Only last Friday (22-05-2015) Neelshan from Bluetechretail calls me to inform me he was coming with the new device to setup of which he didn't pitch up. I received an sms from Telkom with the new account confirmation and one sms that requested me to pay R3000 as a deposit. When this deal was presented to me I wasnt informed of any deposit that need to be paid. How does this deposit come from? does it get deducted from my total debt owing Telkom mobile? Neelshan told i will be reimbursed at the end of the contract which doesn't make sense to me because that R3000 will definitely lose value in the next 2 years. he suggested maybe because I am a FOREIGNER but i have been staying here for the past 5 years and i have accounts. I told him of my old passport BN446797 and I changed it to DN548705 because the later was ******. So i need to know why I should pay a deposit?