R30 Service fee absurd

I bought a pair off shoes plus 2 tee shirts for R928 i took it out over a budget plan of 24 months. after my first account i see thy charge a R30 service fee so if i carry one on my current plan i will pay R720 to me this is just robbing pensioners of there money. i asked for them to change it from a budget to a 6 months plan the lady on the call center said thy cannot do it i would like to know why????