Device Return Upgrade reversal - No feedback

I have received very bad service from MTN. I did an upgrade online on 26/01/2022. I then returned the device on 31/01/2022 to MTN Mall of Africa, I was given a IRMS number and assured that the Sales department would contact me in 3-5 days to process the cancellation so that I can redo my upgrade. Noone contacted me, I called the Customer Care Center numerous times and was sent from pillar to post. I called on 14/02/2022 and spoke to Kameshin who said that the case had been escalated to Tebogo Kekana in Sales and she would get back to me. Subsequently I spoke to a Samuel who gave me the reference *** and said my case was escalated to the Sales team leader Silindile. I called again after getting no feedback and spoke to Kameshin again who now referred me to a number for Retentions Department *** which does not get answered. My account is still showing the upgrade for a device i do not have. It is now almost 3 weeks later and I cannot get anybody to cancel this upgrade, I will end up being incorrectly debited.

How difficult is it to action a simple return and upgrade reversal. How much longer must I wait? This service is unacceptable.