MTN can't get it right

I have requested to have my address details updated three months in a row. Firstly, this can only be done at month's end when MTN sends out invoices. It cannot be done any other time. Secondly, when they updated it, they left part of my old address in it so it cannot be used for FICA purposes. I raised the incorrect address again on the 2nd of September and was assured that it would be fixed by the end of this month. It isn't. I received an invoice with the hybrid email address again (a combination of my old address and my new address). MTN says they are moving from a Telco to a Tech company. Really?