Bad customer service

I am not happy with the services received from cell c costumer care, all Cell C is forever good at is overcharging it's clients and that will never change, if you quiry about the invoice they hangup our calls, why do you still wanna continue being our service provider while you can not provide good services. If Cell C customer services can not help you they must just stop celling us to sell us cellphone contracts coz this is just not what we should be paying for.