regexp to replace multiple lines patern

Text I want to replace is inside wp-config.php:

...
define('AUTH_KEY',         'put your unique phrase here');
define('SECURE_AUTH_KEY',  'put your unique phrase here');
define('LOGGED_IN_KEY',    'put your unique phrase here');
define('NONCE_KEY',        'put your unique phrase here');
define('AUTH_SALT',        'put your unique phrase here');
define('SECURE_AUTH_SALT', 'put your unique phrase here');
define('LOGGED_IN_SALT',   'put your unique phrase here');
define('NONCE_SALT',       'put your unique phrase here');
...

To match all it and replace with HELLO:

sed  "/AUTH_KEY/,/NONCE_SALT/cHELLO" wp-config.php