Unreliable service by UPS

I sent an overnight package on the 13th of December 2018 to be couriered from Midrand, Gauteng to Lichtenburg in the North West. This was done via UPS. UPS handed it over to Global Flight. The package hasn't been delivered till today, 21 December 2018. UPS gives no assistance and no response on emails. I find that appalling as I chose they and did not know of this Global flight. I do not get any assistance from Global Fight at all. There's always say someone will call me back but no one does. I have to call back and explain myself all the time. No one really knows what is happening.