MTN Terrible service and zero assistance

I performed a sim swap for my Note 4 in December of 2014 for an LTE sim card. To this day I have never received an LTE signal anywhere - whether it be in Sandton City or Auckland Park, all the places MTN claims are LTE covered regions. I have called the call centers many times to be assured that my cell phone number and sim card is activated on the LTE network. My sibling has the exact same phone and performed a sim swap the very same day and gets LTE practically everywhere - even side-by-side the phones will show his with LTE and mine without (settings on both devices are identical). I have tried to get assistance on this issue from the call centers (no-reply) to going in-store. Still no help. In-store I was told to call the call centers (that don't work) and told that she was not able to check the system whether the sim card and number were properly activated. What's the point of going in-store? Eventually I went to twitter to share my complaint. MTN service twitter account responded asking for my cell phone number. I responded and it has been radio silence ever since. I am utterly disappointed with the service I've been getting, extremely disheartening.