MTN Upgrade Ignored

I am a contract owner due for an upgrade (currently with a Nokia 7 Plus, a phone notorious for charging port issues). The stress of having a phone that dies or won't charge has been extremely frustrating but I've pushed through to reach this upgrade date.

The MTN website, however, does not recognise my number as a valid contract (this is the same number I've had for at least 20 years).

I have now been waiting for contact from retentions for a week. When will MTN allow me to upgrade and have a new device (that works)?

Considering switching over to a competitor.