Login with Facebook cant change my password

Good morning. I login with facebook, and now i want to log in with a codingame user, but when in try to change the email i cant, also i cant change the password. Any idea?

if you have access to your Facebook email address, you can use the “forget my password” button on /start page. It will send you an email, so you’ll be able to generate a password for that email. Then, log in with it and you’ll be able to change your email.