configuring database connection results in Error :host 'xxxxxxx' is not allowed to connect to this MySql server code example

Example: host not allowed to connect to this mysql server

mysql -u root -p
    -- root password

    CREATE USER 'username'@'localhost' IDENTIFIED BY 'password';

    GRANT ALL PRIVILEGES ON *.* TO 'username'@'localhost' WITH GRANT OPTION;

    CREATE USER 'username'@'%' IDENTIFIED BY 'password';

    GRANT ALL PRIVILEGES ON *.* TO 'username'@'%' WITH GRANT OPTION;

    FLUSH PRIVILEGES;

    EXIT;