incorrect billing logged in April still no feedbac

I was incorrectly billed,for the month of April I called on the 29th and was told a billing query will be logged and resolved with 10 days after numerous calls I was told Mtn is stricking it will be delayed,I called 10 July and was told my initial billing was closed as no one attended to it .a new billing query was logged and yet still no feedback .this is outstanding from April I want feedback as this is possibly the worst service and customer promise is not being met.how is this complying toTCF?