Headlight wiper makes itself independent

Hi, guys.
the wiper of my left headlight stays somewhere after use but not at the final position. As far as possible, the limit switch could be, but the curious thing is that the wiper is standing elsewhere after each engine start, until it eventually goes through by chance at the final position and stays there. Until the next headlight cleaning.
The problem is that it is not a problem. has a solution ?

MfG Norbert