Advice on using contact form 7 hook

Hi,
I have written the following codes:

// define the wpcf7_mail_sent callback 
function action_wpcf7_mail_sent( $contact_form ) { 
    $temp1246 = get_post_meta( 1246, $key = 'ID', TRUE);
    $temp1246 = intval($temp1246) + 1;
    update_post_meta( 1246, 'ID', $temp1246 );
}; 
         
// add the action 
add_action( 'wpcf7_mail_sent', 'action_wpcf7_mail_sent', 10, 1 ); 

What the code does is that it will increment a page’s custom value by 1 every time a contact form is submitted. But the problem I have now is that I only want a specific contact form to trigger this code when it is sent, not all the contact forms (I have a few contact forms in the site powered by CF7).

May I know how can I adjust the codes above so that it is only triggered when the contact form (id = ‘1000’) was sent for example?

Appreciate if anyone can assist, thank you!