Sort Title

I find that the Sort Title is not able to be changed for a movie. My example is the movie “London Has Fallen”. It does not appear under L as I would think, but under O for “Olympus Has Fallen”, which is the name of the series it is assigned. The Sort Title appears to be directly tied to the assigned series and its number within the series. Is there something I might be missing? Specifically, is there a way I can change the sort title so a sort by title listing appears in order of title?