Incorrect charges

After numerous attempts to try and get hold of them,To ask about my account that is repeatable incorrectly charged and each time /month I call they said they will fix. I am charged for a prepaid meter I dont have ,Actual readings are done and basic charge is charged based on the size of the meter i have yet they add availability charge and & Vacant erven charge. I am sick and tired of being ****** by the COCT.