iSpot is still beating you - you've entered the zoological name by hand, and mistyped it. (Or, on reading the comment thread on the observation, HB mistyped it.)
Go to the vernacular name box, enter mullein, and select the option that corresponds to Shargacucullia verbasci. Or enter Sha ver into the scientific name box, and do the same.
In general, iSpot doesn't expect you to enter a full name, just enough to narrow down the possibilities. Unfortunately it is sufficiently slow that you can type the full name before the drop down box kicks into gear.
You have to remember that iSpot has no semantic understanding of names, beyond the mapping of names to groups. (I've been using computers long enough that search engines has no semantic understanding when I started using them.)