Terrible service and no feedback at all

On wednesday the 10 June 2015 I went to the Vodacom outlet below Centre Court in Pavillion. I first went into the store and said i needed a LTE data modem urgently, and also mentioned that i have had a previous bad customer service from another service provider and therefore cancelled with them and came to Vodacom. Upon arrival i was assured that i was in good hands and they will submit my documents for approval. The guy that was helping me said they had no stock of that modem and would order it for me first thing in the morning. I was told that stock would arrive by Friday, latest Monday. Everyday i have had to phone in and ask what is the latest as they have not once until this day returned any promised calls as they said they were too busy with other customers (so what am i then?). Stock apparently arrived but no LTE modem was found. When i phoned in again today i spoke to the manager as whose tone of voice i could hear was irritated and clearly not interested as she said would personally call me by 2pm today. I however am still waiting for her call. Constant 6 days of nagging and still have got no where.