Avoid IFTT duplicate posts with XML RPC

I’m new to WordPress and I’m not a developer. I’m running an IFTT applet that posts a WordPress post each time I upload or like a video on Youtube.

There is a bug with IFTT. It often posts the same post 2 or 3 times.

Therefore, I’d like to avoid duplicates before they are published. I read on forums that I needed to add a XML RPC plugin.

I tried this solution from WordPress StackExchange.

<?php
/**
 * Plugin Name: Avoid XML-RPC Post Title Duplication
 * Description: Prevent duplicate posts when doing wp.newPost via XML-RPC
 * Plugin URI:  https://wordpress.stackexchange.com/a/157261/26350
 */

add_action ('xmlrpc_call', 'wpse_xmlrpc_call' );  /////

function wpse_xmlrpc_call( $method )
{
    if( 'wp.newPost' === $method )
        add_filter( 'xmlrpc_wp_insert_post_data', 'wpse_xmlrpc_wp_insert_post_data' );
}////

function wpse_xmlrpc_wp_insert_post_data( $post_data )
{
    // Check if the post title exists:
    $tmp = get_page_by_title( 
        $post_data['post_title'], 
        OBJECT, 
        $post_data['post_type'] 
    );

    // Go from 'insert' to 'update' mode within wp_insert_post():
    if( is_object ( $tmp ) )
        $post_data['ID'] = $tmp->ID; 

    return $post_data;  
}

I added the code using Insert PHP Code Snippet WordPress plugin.

But it doesn’t work for me. I still have duplicate posts coming in.

I also tried to create a plugin file and it doesn’t work either.

Is this code working?

The page I need help with: [log in to see the link]