Tie note between natural F (half note) and F sharp (quarter note) not correctly linked

When creating a tie note from e.g. a natural F (half/quarter/... note; does actually not matter) to an F sharp ('length' of note does not matter), the tie is not correct. 
I stops in the middle between the 2 notes. However, when changing the second note to e.g. an B sharp, the tie is correctly linking both notes. It seems to only affect the same notes (except for the natural/sharp/flat character)