Paul Smith tries to force-sell unwanted items

I purchased a pair of formal pants (not on sale) from Paul Smith on Monday. I wore them today (Wednesday). I like the pants so much I went to see if there was a matching suit jacket today. There was. I asked to purchase it. The salesman said that the jacket could not be sold without a matching pair of pants. He agreed that the matching pair of pants and the pants I was wearing and had already purchased were the same. I naturally did not want two pairs of the same pants. I explained that I should not be forced to buy the same pair of pants again when I wanted only the complete suit. The salesman said the pants with the jacket did not have their own barcode. I offered to return the pants I was wearing in exchange for the (same) pants that apparently are not barcoded. The salesman phoned his manager. Still they refused. I buy many clothes from Paul Smith. I was wearing a pair of their shoes and socks. I feel that this is a despicable way to treat a customer, let alone a regular customer.