Very bad service after upgrading a contract

I recently upgraded my data contract via online sales with Yvon Masobe The wifi router was delivered but it is not working. from day 1 it did not power on when plugged on charger.

I have gone to two different MTN shops, i.e. Boulders and Mall of Africa that confirmed that it is faulty but could not help as the upgrade was done online. Made several calls where I got sent from pillar to post; about 6 six people passing my call from one department to the next. It is very disappointing that MTN has deteriorated to this. Customers should not have to struggle like this to have access to a paid service. I am contemplating cancelling the upgrade as it really worries me that I will be treated this way every time there is a need for me to get support from MTN. aftersales is really horrible.