Permalink Issues

Hi,
I recently started to have issues with a page on my website. its published but i haven’t put it on the menu or anything like that. my website is http://www.fotocause.org
and my page should be http://www.fotocause.org/kollaborativ but its goes to a separate blog page or something like that but if you change the small “k” to capital “K” its cool. please let me know how this can be resolved.
Cheers,
Geet Sharma