Still no service after a month

One of our company cellphone's invoices are no longer appearing on our profile. Tried phoning MTN on 1 Sep, but you cannot speak to anyone. Sent a query and got a reply that someone will assist, have been sending follow up emails for the past month to see when the error will be fixed and get a story every time that they have escalated it to the business department. How can you still not have attended to this after a month? Are you that understaffed or does no one there do any work?