download link redirecting to someone else’s website?

I have a download link for a zip file here: http://diffree.com/?page_id=11 but when I check and click on it, it seems to be redirecting to someone else’s website! I emailed them about it, as I suspected they tell me it’s me and the link must be wrong and they are the default page (100webad.com) ? They say they are affiliated with my hosting service. Since WordPress is creating the link for me, how do I fix this? I checked the link and made sure it matches my ftp files and everything seems to match.