Misleading and False advertising

Tried buying a Mason office chair on their website which is valid until 8/06 but when i go onto pay for it im get the prompt asking me to remove it from my cart. When i call customer service i get told sorry nothing can be done and they cant tell when stock of the chair will be in and when i ask to speak to someone higher up and got told sorry not even that person can help me so when i explain to the person that this is false advertising and misleading the person then tells sorry nothing can be done and that i should refer to the terms and conditions on the advert. What an absolute shocker . Hifi corp needs to be held account able for this.