Incomprehensible business practice

Where do I go from here?

I app**** for an upgrade through MTN Direct. Once I received the phone, there was a problem and I sent it back the next day. Now, nobody at MTN is able to help me cancel the upgrade except, Zahrah Heynes. The one person who did my upgrade.

How in the world is this possible? Only one person on the entire MTN staff and how should I locate this person to cancel the upgrade? I've made numerous calls and wasted hours trying to sort this out. Everyone just passes the responsibility to Zharah, but can't tell my how I should find this person.

Ridiculous.