If one of the sellers of the items in your cart is on vacation, you will get that error message when adding a new item to your cart. For best results, remove or "save for later" all the items in your cart. Starting with an empty cart, add an item you want to your cart and then check out.

You'll see Add to cart beneath the Buy It Now button on any fixed-price listing.

You can also save items for later and only pay for the items left in your eBay shopping cart, or click Buy It Now from the listing page to purchase individual items immediately. When you add items to your eBay shopping cart, you won't be committed to buy these items until you check out and pay for your purchases.

To add an item to your shopping basket - opens in new window or tab, simply select Add to basket beneath the Buy it now button on any fixed-price listing. To view the items you've previously placed in your basket, select the basket icon at the top right-hand corner of the eBay site.