disgusting liers

Vodacom puts up premiums and prices without informing you AND do not live up to the services promised yet I have to pay premium higher than what was agreed on for 24 months. fortunatemy upon listening to recording of their call to me they heard he fibs however I still do not receive the promised deal. now get another call which again proved how sneaky they are. the cost to buy data on their system is NOT same as on my phon. oh sorry price has gone up we just haven't informed u or updated the system for customers. most unprofessional. how can I get out of this contract? how come they have a right to spindle and I must just pay???