Can’t change “other” settings in Clubs.

I started a clubs to play with my lads. When one of my friends wanted to join us, he can’t apply to the club because we don’t accept transfers. When I wanted to change the transfers settings, I can’t change any settings in the “others” section, I can only change the team code (three letter name or abbreviation? I don’t really know what it’s called.)
Anyone knows why this happens and how can I fix it?

Thanks.