False advertising and failure to fulfil on sales

This company seems to have a trend of cancelling orders when items are on promotion with no further explanation. The item will then still be available online but at a higher price, especially furniture items. This is my personal second time experiencing this with them. The sale will only commence once it is no longer marked down. I then checked other reviews on their app and it seems to be an occurrence for all customers. They're not out of stock, they'll just not sell at the promoted price.