Go to cPanel and set a new password for the database (you don't even need to have the current one, to reset it), then update the config.php file with that new password - but as already stated, the pw is in the config, in plain english (not encoded; it's encoded in the database itself, but not the config.php file).
Your "admin" password for Machform should NOT be the same as the database user & password! They should definitely be separate details.