Hi Jennifer, as i am seeing in your website,
You have made some customization in the product details page. Such as; disabling the "zoom" effect and replacing it with the classic modal popup. Most likely, you deleted some other lines to which cause the "slide box" not functioning.
Slidebox and the zoom effect are meant to be working together. Any kind of "touch" might break the harmony (just like what happens in your website).
We don't provide free support about custom modifications or a failure after making custom modifications.
So please retrieve your changes and get back to original PureMart (for this purpose, i would suggest you to get the latest version of PureMArt (v3.5) it has been released yesterday and includes lots of improvements). If the slidebox still don't work with the "untouched" PureMart, then i can provide you free support until it gets fixed.
Regards.
Forum Support.