There are generally three issues we see with password resets not working. You can change your password in the advanced settings page
1) Incorrect email. If your email address is wrong on the site then you will not receive the reset password. If you have received the email then this is not the problem. If you have provided us with an innacurate email address then we can't help you unfortunately.
2) Confused browser. Internet browser's are known to get confused sometimes. :-) If you clear your browser cache and restart the browser it will 90% of the time resolve the issue.
3) Wrong reset email. If you reset your password more than once you need to make sure you're using the latest reset email you received.