Shipping the wrong stock twice.

I have ordered a pair of shoes from them, a UK8 size. That was the options on the website. I have the shoes a couple of days after ordering, and they have sent me a USA 8 / UK7 size. Log a return and ask for the correct size. On the 2nd order a week later and a couple of emails, they sent me the wrong size again. I can't believe they can't even read a picking slip to shipp the correct item.