incorrect renewal of a contract for data i dont use

i have been phoning the call center cancellations and dispute since September 2020 and not able to get anyone to phone me back even though i keep on being told they will and investigate. i have been charge for data i dont use on the number ***. i got hold of the manager Onkemoya who assure me he would investigate and come back to me and he never did . i have phoned at least 10 times and i have kept the names of all the consultants i spoke to who assured me the matter was under investigation and they would come back to me which they did not.