Not Working

Does anybody have any idea why I can’t buy “Columbo – Series1-7 – Complete” on this site? It says it’s been added to my shopping cart, but when I view the cart it says “You have 0 items in your shopping cart”. Other items work perfectly, it just seems to be this one.
I emailed the site yesterday but have not yet had any reply.
If anyone has had a similar problem, or knows how I can fix this, please reply.

A quick update, now whenever I add any item to the cart and try to view the cart, a blank white page comes up saying there is a problem and Playback have been notified.
Sorry for the double-posting.

Hi there, sorry for the inconvenience, our site is updated from Amazon, this product is no longer available, new, from Amazon unfortunately due to a technical glitch this was not updated on the site. 1 to 7 has subsequently been deleted from the site but you can order Columbo Season 1 to 8 at a really great price.
Sorry again for any inconvenience.