Lost your password – but new doesn't work

Yesterday I changed from
http://mywebsite.com
to
http://www.mywebsite.com
without changing password at the same time. I have now managed, via wp-config.php to restore back to original url address by inserting this 2 lines
define(‘WP_HOME’,’http://mywebsite.com’);
define(‘WP_SITEURL’,’http://mywebsite.com’);
B U T
i don’t manage to log back in. So when i click on
Lost Your password, and get an email with a link, where I have to type my new password 2 times, and then try to login – NO WAY.
WHY isn’t it possible to login with the password I just have typed in? Feeling a bit lost being expluded from further editing the content.