ENTREPO sells defected products and refuses to fix

I have been waiting over THREE months now for a response from Entrepo after selling me a defected product, bought a biofire heater and in order to assemble it, you need 8 special *****s, I only received 6, so it is not secure and looks incomplete -I called, called again, visited the branch 3 times and I have been to their V&A store where I was met with rudeness and left before dealing with the issue, I went back to the Cavendish store again and Franco promised he will sort it out and he agreed that it is outrageous and will escalate it to head office. However, this did not help either. There is something like quality control specially if you want to sell upmarket product. I have bought a heater that I have not been able to use yet and winter is almost over!!