plugin to send email on attachment page

Hello forum. I am trying to make the following “plugin” to just send emails when a comment is made on the attachment page.

I tried putting the function code inside an if is_attachemnt condition and it doesn’t work either…

Does anyone knows the right way?

Thanks

function notify($comment_id) {

$user_email = 'example@gmail.com';

$subject = $comment_id . get_option('blogname');

$t1 = 'Someone commented on a your picture';

$t2 = "click here to see the comment";

text = $t1 . $t2;

wp_mail( $user_email, $subject, $text );

}
add_action('comment_post', 'notify');