No upgrade after three months, which they promised me.

Three months ago mondo offored me a cellphone contract with vodacom, with a promise that after 3 months i can upgrade to a much better cellphone. I called Mondo twice with no success about my query,they didnt even get back to me,i feel i was ****med into this contract, not even an email or a call for the reason why they dont want to upgrade my cellphone after the sales lady promised me high and low, that after the three months i could get a better cellphone.Very dissappointed in Mondo