Where can I find JLPT N3 part 2 by mathieuRobot???
Thanks
You can easily find the courses of any given user by going into their profile and checking the list of courses taught by that user, i. e. in your case:
https://www.memrise.com/user/mathieuRobot/courses/teaching/
Looking at the course list it seems that Mathieu simply doesn’t teach part 2. This may be due to the course being private/unlisted or because it simply doesn’t exist (anymore).
Now to contact a user you could try and tag them here, i. e. @Tamagoyaki51. However, this requires the user to have a forum account, which @mathieuRobot doesn’t have. So I’m afraid you’ll probably just have to skip to part 3 instead.
Oh, I forgot one last thing: the links to courses follow a certain pattern. In your case, I was able to construct the link to the second part of the course, so it’s not listed but accessible to persons who know the link (for whatever reason).
IOW just go here and start learning:
Bon courage !