Pending phone upgrade since 4th August 2029

I would like to lodge a complaint , I have been ruin ring to perform a phone upgrade( *** , pending phone upgrade) since the 4th of this month up until today I haven't received any response regarding my upgrade the last manager I spoke with told me to send a copy of my ID and I did but no one called back and when am calling 135 they taking me back and forth either they send me to a different line or my calls are being dropped , I have been patient with MTN I don't know what to do anymore ...