MTN Shocking service and Charges

I recently app**** for a Black friday deal which I have since 2017 so I was upgrading that deal via the Mtn website. The deal was on my wifes name so everything was approved and we were notified via sms that the sim card would be delivered to her work address. The black friday deals were due to expire on the 9th December 2020. During the week of the 9th I kept receiving calls from the courier company to deliver the sim card and advised them that they need to call my wife so they can deliver to her.She kept on calling them and the delivery service said they will contact her, this went on for a week and eventually they did get hold of her and arranged for delivery on the following Monday. the sim card was then re called to the warehouse and never end up being delivered to us with the contract not being upgraded. Mtn then moved my contract to a month to month deal and now want to charge me an exorbitant amount as I am on a month to month for their stupidity of not delivering on time. I have also requested settlement letters from Mtn consultants for my other contracts, they will advise that its done, since that department closes at 5pm everyday automatically at 5 01 the call gets cut and we don't receive the letters. I have been a loyal client for over 10 to 15 years and will not except being overcharged for Mtn pathetic service.