When I visit profile of any user and try to click any other section of that user like: all activity, all questions, all answers, then it returns an error "page not found" and link changes to "https://mysite.com/index.php?qa-rewrite=user/Gudda/answers". (please note that I have set (/123/why-do-birds-sing (requires htaccess file) URL structure, which is already working fine for others, like question link).

Even, in my (admin) account, these sections are not working.
Is it some database error or anything else, could you please resolve this issue?