Deceptive Online Purchase

Game has a halfday special on today. I saw a Sinotec 42" Android tv for online purchase only. there was only 1 item available i proceeded with all prompts to check out and just before loading the card information the system did not allow me to check out due to a technical fault on their end. It kept saying the is a reduced amount left. But when i went back to cart it showed the item was still available. The special is only for today and included free delivery. ironically after me emailing its showing the item as not available anymore. i called in for assistance and was placed on hold nobody took my call nor did I receive a response I messaged on various platforms including Facebook. I provided screenshot evidence and had a response on Facebook that the item was not available. But the screenshots clearly show it was available. Very disappointed.