Useless service from MTN

I received sms from MTN saying I was due for an upgrade early in the new year. I was contacted by their agents saying I was due for an upgrade. I checked my MTN app and it said I was due for an upgrade. Istore Eastgate checked and said I was due and did the upgrade on the 10/09. The end of September MTN deducted R26049,64 from my account without a mandate. They said I did an early upgrade yet at Istore on the MTN system it said it was a normal upgrade. 25 days later, with the phone been returned and the upgrade been reversed by Istore and numerous reference numbers from MTN the problem has still not been resolved. All the call centre does is escalate and that is where it ends. Have requested a call back but to no avail. The early cancellation in their eyes was charged at almost double the cost of an IPhone 13 at today’s value. Service, they don’t know the meaning of it. This is how they treat their long term clients. Absolutely shocked at the service. Will have no alternative but to go to the ombudsman and lodge a complaint.