Adding a random string as slug för CPT

Hi!

I’m trying to add a random string as slug for a CPT. I’m not a programmer so my solution after googling a lot is to first add a new custom field called cv_random_string and creating a random string that i fill it with. Then I use the value of that field and use it as slug. This works fine when creating the post. But when I update the post the random string is added once again to the slug. This only happens once. https://www.mysite.com/cv/v6ji4puptusr becomes https://www.mysite.com/cv/v6ji4puptusr-v6ji4puptusr/.

I would like it to only have the random string appended to the slug once. Also, maybe it’s possible to not use my two step solution with the random string field? 🙂

What I want is basically to add a random string as slug in the CPT cv.

This is the code I use:

/** Generate random string */
function wpwebguider_random_string( $length = 12 ) {
    $str = "";
	$characters = array_merge(range('0', '9'), range('a', 'z'), range('A', 'Z'));
//    $characters = range('A','Z');
    $max = count($characters) - 1;
    for ($i = 0; $i < $length; $i++) {
        $rand = mt_rand(0, $max);
        $str .= $characters[$rand];
    }
    return $str;
}
/** Set Dynamically ACF Field Default Value */
add_filter('acf/load_field/name=cv_random_string', 'wpwebguider_acf_load_random_string_value', 99, 1);
function wpwebguider_acf_load_random_string_value( $field ) {
    $random_code = wpwebguider_random_string();        
    if( $random_code ) {
        $field['default_value'] = $random_code; 

    }   
    return $field;
}




/** Add random string as slug, this doesn't work */
function acf_title_companies( $value, $post_id, $field ) {

	if ( get_post_type( $post_id ) == 'cv' ) {

		$new_title = get_field( 'cv_random_string', $post_id ) . ' ' . $value;
		
		
		
		
		wp_update_post( array(
			'ID'         => $post_id,
			'post_name'  => $new_title,
			)
		);
	}

	return $value;
} 
add_filter( 'acf/update_value/name=cv_random_string', 'acf_title_companies', 10, 3 );