"Licence" is a British spelling. It is not incorrect at all. Different countries will use their nation-specific spellings of common words, even if it is part of a title.
However, in the case of this Bond flick, it is Licence with a "C-E" as the official title even in the U.S. Just check IMDb for proof. The Bond producers may have opted for this spelling for any of many reasons... 1) Bond is British, it works; 2) "License to Kill" was already a movie title at that time that came out in 1984 starring Denzel Washington; 3) well, there are likely others that I just cannot think of right now.
Don't worry, you're not the only one who has been misspelling it. I've been using the "S-E" spelling each time I've typed it so far. Guess I'd better change.
This would definitely explain why I couldn't find it on Netflix. I kept looking for "License" and they have it under the "C-E" spelling."
Best. Bond. Ever.