How to publish a notification in the dashboard ?

See:
https://www.google.com/search?q=wordpress+plugin+dashboard+widgets

Thanks. That’s good, but not exactly what I wanted, unfortunately ??

Nobody knows ?

This in your theme’s functions.php will work:

function my_admin_notice() {
  echo "
    <div id='my_admin_notice' class='updated fade'><p><strong>".__('This is meant for you.')."</strong> ".sprintf(__('Please call me to discuss your options.'))."</p></div>
       ";
  }
add_action('admin_notices', 'my_admin_notice');
return;