This means that there is some kind of restricted shipping condition on the item that cannot be arranged through Vine. The most common ones seem to be that the item is “geo-locked” to a certain radius around its warehouse in order to keep shipping costs low, and/or that the item would need special delivery services that cannot be scheduled through the Vine interface.
This error can come up regardless of the physical size or monetary value of the item. It is not indicative of an issue with your Amazon/Vine accounts.
Occasionally this error can be overcome by choosing a different shipping address, but some items seem to throw the error for everyone regardless of location.
