I'm not certain what works because I was doing a little of everything to get it to work. Try to refresh the page. That may take a couple of tries. If refreshing multiple times doesn't work you may have to totally empty your cart and start over. If that doesn't work, you may have to empty your cart, totally close down the web page and then go in again fresh. It took me several attempts of messing around before I finally got the 4 items I wanted into the cart. Then it took me a couple stabs before my PayPal payment would register and go through. There I just kept refreshing the page. I didn't dare mess with the cart once I finally got it where I wanted it. For me, the site wasn't very user friendly and it looks like others are having the same issues.It won't let me add more than one item to my cart... how did you guys get it to add more?