MAMP installation change password
Inside: /Applications/MAMP/bin/phpMyAdmin, there is a file named config.inc.php.

Inside of that file in your favorite text editor, you should be able to search for $cfg['Servers'][$i]['password'] and then modify the text in single quotes. (Which is 'root' by default.) Change that to whatever you changed your password to, ensure it's quoted as necessary, and refresh. You should instantly be connected!