Call centre overloaded and just drops calls

After waiting 1h and 10min on hold to upgrade my wife's contract the service centre dropped the call. I would like a MTN representative to call me and explain how this is acceptable (this is not an isolated incident). If call rates are high, take numbers and call your customers back; do not let them sit on the call not knowing when or IF it will ever be answered. BTW, calling again and selecting to cancel my account just straight away cut me off and dropped the call immediately.