Useless customer service

I've upgraded my phone and on their delivery the courier guy couldn't give me my phone due to physical address not matching, how did they get the address wrong and how did they deliver the last time? ok had to phone customer service to fix that and now after the whole week no phone delivered, so i send them a fb messenger and was told they don't have stock, then i phoned and i was told its been processed, and the email response was that it was sent to couriers. It so amazing how all of this agents have different responses on my upgrade. I'm actually cancelling this contract