No personnel available at upgrade department

After trying to upgrade since the 1ste of November to the iPhone 6 ,they still don't have stock,they told me everyday since then that the stock is coming tomorrow ,it's the 4th of December now,still no stock.This morning I decided on another phone and called the call centre,I was informed that no one from the upgrade department was available,I asked how is that possible and I was told its not my business?? How is there no one available?