Taking long to deliver my handsets

I upgraded my 3 lines on my mtn contract through the phone on the 1st of August and the consultant helped me efficiently,was told the couriers will contact me within 3-10 days and up to now there is no contact from the couriers or mtn to tell me where my phones are.I have phoned mtn several times all they tell me is the couriers will contact me and I am getting frustrated at waiting for my devices with no one telling whats going on,please solve this I have been waiting for long.