publish_post calling twice

I created a function to automatically post an updated or published post to Facebook. The code as it is works exactly as expected, see:

function enviar_post_facebook() {
    
        global $post; 
    
        $ch = curl_init();
    
        $url = 'https://graph.facebook.com/v19.0/adoromaquiagemweb/feed';
    
        $access_token = '22222222222';
        
        
        $intro = get_post_meta($post->ID, '_yoast_wpseo_metadesc', true);
        
        $link = get_permalink($post->ID);
    
        $options = array(
            CURLOPT_URL => $url,
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => 'message='.$intro.'&link='.$link.'&access_token='.$access_token,
            CURLOPT_RETURNTRANSFER => true
        );
    
        curl_setopt_array($ch, $options);
    
        $response = curl_exec($ch);
        
    
        curl_close($ch);
    
    
}

add_action( 'publish_post', 'enviar_post_facebook' );

However, if I insert additional text in the $intro variable, for example: $intro = get_post_meta($post->ID, '_yoast_wpseo_metadesc', true). '#hashtag1 #hashtag2 #hashtag3';

If I do this, WordPress calls twice, so that the first time it sends a publication to Faebook with only the values of “#hashtag1 #hashtag2 #hashtag3” and the second time it sends it correctly with the meta description and hashtags.

I can’t understand why this is happening. I’ve already done several tests to check that the meta description is not empty before calling the Facebook API. Change “publish_post” to “save_post”.

Anyway, I just add text to my $intro variable that triggers two publications on Facebook.

Can someone help me ?