Where to now? Really shocking service and an entrenched attitude of passing the puck

On the 31st of May, my MTN LTE contact was downgraded from MTN Home Pro, to MTN Home starter without my knowledge or consent..

I proceeded to call the MTN helpdesk, just to find out that I would have to contact sales department in business hours as they where the ones that made the change.

I then proceeded to call them on Monday and was shunted back and forth between every single department within MTN with no resolution, or reason given for the Obvious mistake made by an MTN employee.

On Tuesday I opened a ticket after phoning again (about 4 hours on the phone in total) and the response to the ticket was that the migration was done by a different department and the thicket was summarily closed.

I then phoned again asking what the correct department was to speak to to get a resolution to this problem.

I was again shunted around from direct sales, to legal, to retentions, to some unpronounceable department (Something like Modo, or Mojo) and then to billing (Another few hours on the phone)

I ended up opening a new ticket with the billing department asking 2 things, firstly, that the correct department to contact me so the this obvious error could be resolved, and secondly to find out where and how this change was done on my account without my consent.

The response the next day (Today) was "the customer did the migration in store". I then proceeded to ask the lady which store and she was unable to answer me.

I have not been inside an MTN store in over a decade...

So now a new ticket has been opened, asking what store?.

In 24 for hours the answer if probably going to be, we don't know...

No one inside MTN is willing to take ownership of this problem to get my queries and issues resolved.

So to summarize:

First I was told its the sales department. Then I was told its ad different department (The unpronounceable one I mentioned earlier) Then i was told that it was done by myself in a MTN store, even though I haven't been in one. And when asked what store they cant tell me...

In it's self this would not be the end of the world, however, our IT business relies on having a stable, always-on Internet connection and at the smallest package that they have forcibly put us on, we will reach their [un] fair use policy within the next day, thus causing irreparable damage to our business, as we cannot trade if we do not have bandwidth to do so.

Additionally, I was looking at Migrating All our business cell contracts across to MTN, but with the absolute appalling service I received from MTN I am thinking of just leaving everything as is...

Please help.