URL doesn't work issue

Hi, I would like to know your suggestions about the problem of my website. I have 1 URL which already rank in google however it is already down now because the URL suddenly broken. This is the URL http://www.textbooksocial.com/used-college-textbooks/ but now it redirect to http://www.textbooksocial.come-textbooks/ which is not valid URL.

I already check the permalink but it is correct still the permalink is http://www.textbooksocial.com/used-college-textbooks/.

Please help me with my problem.

Sincerely,
Erwin