MTN Kolonnade bad service

I had my phone for 10 days and it just stopped working. I took it to MTN in the Kolonnade on the 14/03/2019. They send it for assessment and promise that it would take 2 weeks. The assessment in not done yet after 2 months. Every time a phone for an update I'm told they are waiting for a number from the assessment centre. I've even been ask to put this on hellopeter because they cant get answers from there assessment center. Been posting it to Mtn customer center to and nothing no call to follow up.