No delivery

I upgraded my contract through MTN direct. When I followed up with MTN they say the new phone is with RTT, the delivery company. When I speak to RTT, they say MTN must still authorize the delivery. When I speak to MTN again, they say they have authorized. RTT, same story and round and round we go. They have admitted there is a known system issue, but seem incapable of finding a solution. When I try to phone MTN now it just says \We're experiencing network issues