Here's what helped me when I couldn't use Facebook to log in:
Step 1: Go here -> www.heyshell.com/cot/
Step 2: Click on ID -> Settings in top right corner
Step 3: Your profile login if you used Facebook to login will be posted there. Mine started with 'fdfb' followed by a bunch of digits and ending with @feidou.com. That is all part of your login.
Step 4: Find the e-mail section. Reset your password. Your login will still be that horrendously long thing.
Step 5: Login with your new password.