Here is the explanation in their email message:
"Hello from Amazon.com.
We are sorry to report that we will not be able to obtain the following item from your order:
"Fingerworks TOUCHSTREAMLPDVORAK Touchstream Lp Dvorak"
http://www.amazon.com/gp/product/B00074JPJ6
Though we had expected to be able to send this item to you, we've since found that it is not available from any of our sources at this time. We realize this is disappointing news to hear, and we apologize for the inconvenience we have caused you.
We have cancelled this item from your order.
While this item is not available directly from Amazon.com, you may be able to purchase it from one of the many other sellers with product listings on Amazon.com. Please click on the link above to visit the product detail page.
If the item is available from a third-party seller, you will see a "Used & new"
link on the product detail page that will provide a list of merchants currently selling the item.
Note: If you took advantage of a promotional offer when placing this order, this cancellation may affect your order's eligibility for that offer. If this is the case, please contact customer service; if we confirm your original order was eligible, we'll reimburse you for the value of the promotional discount. However, we can't reimburse you for rebates offered by manufacturers or by Amazon.com.
Your credit card will NOT BE CHARGED for this item because you only pay for items when we ship them to you.
Your order is now closed."