Worst online experience ever!

What a dreadful experience. I ordered for the first time from Evans about 3 weeks ago. The website was advertising an additional 20% off online orders, which required you to enter a discount code at checkout. I duly entered to code, only to find that the discounted price didn’t update. I wondered if there would be a further screen that showed the end price, but no, the purchase completed at the full price. I immediately found the ‘contact us’ section on the website, which included a drop-down subject heading for ‘discount was not applied’. I sent the email, and heard nothing. Another email: still nothing. A formal complaint: zero. While I was waiting I received an email to say my order had been shipped, but nearly 3 weeks later...you guessed it. Nothing. As far as I’m concerned I have been ripped off. My advice is DO NOT use this site if you are ordering from OS. Customer service is worse than useless.