MTN - a company that knows how to waste time

I recently made an inquiry as to when I can upgrade my contract with MTN and was told by the saleswoman at the Tyger Valley branch on Sunday, 23rd of February 2020 that I can upgrade on the 1st of March 2020. Just to make double sure, I contacted the call centre yesterday (29 February 2020) and they also confirmed that I could upgrade on the 1st of March 2020.

I went back to the Tyger Valley branch this morning (1 March 2020) only to be told by the salesman that I can only upgrade on the 7th of April but he could not explain why. I would never have spent an hour of my time waiting just to walk out the store empty handed. After phoning the Cape Gate branch, I was informed that contract upgrades can only be done after 21 months and no longer after 20 months.

Was this ever communicated with the customers, and if so, why have staff both in store and at the call center been allowed to give false/incorrect information?

As a result, I will be cancelling my contract with MTN as this is not the first time I have left the Tyger Valley branch red-faced and irritated due to the incompetence of the staff.