Business ProfileforAllposters.com

I received several emails pertaining to Black Friday sales on November 25th 2022 from allposters.com. Their emails said EVERYTHING on their site was 55% off. Every single item. I had been searching their site for several weeks to purchase some cardboard/ stand *** props and decided to wait until Black Friday to get them on sale. I clicked on one of the 55% off emails from them and started happily shopping for all the items I was going to get 55% off . I had several items in my shopping cart and went to check out. My order was over $400.00 . It would not give me the 55% off. I tried for an hour to get the sale price. Very frustrated , I emailed the company because there is not a phone number anywhere on their website. Their response was the items in my cart were already everyday low priced and wouldnt give me the 55% off. The price wasn't any different than it has been for the last month that I have been looking at them. I was not happy and responded to the email that this is false advertising and it says every single item is 55% off. I find this to be wrong in so many ways. I would like some input on how to make them give me the 55% off and stop them from false adverting so this doesn't happen to other people. I have saved the emails and hoping you can guide me on how to go forward with this please. I am not looking for settlement or anything. I just want them to honor the 55% off from my order.