Creating Commissions based on Products

Good Afternoon,

I am trying to setup different commissions based on product types for specific products. The default commission is 5%. I have 3 products that I want to set commissions for differently with a rate for each as per the following:

• Product ID: 4537. commission 50%
• Product ID: 4540, commission 20%
• Product ID: 4542, commission 35%

Here is the code that I have added to my functions.php in the child theme. The site is still using the default commission rate.

<?php
add_filter( 'yith_wcaf_commission_rate', 'custom_yith_wcaf_commission_rate', 99, 3 );

function custom_yith_wcaf_commission_rate( $rate, $affiliate_id, $context ) {
    // Get the global WC Cart
    global $woocommerce;
    
    // Iterate through each cart item
    foreach($woocommerce->cart->cart_contents as $cart_item_key => $cart_item) {
        
        // Get the product ID
        $product_id = $cart_item['product_id'];
        
        // Set the commission rate based on the product ID
        switch($product_id) {
            case 4537:
                $rate = 50; // 50% commission
                break;
            case 4540:
                $rate = 20; // 20% commission
                break;
            case 4542:
                $rate = 35; // 35% commission
                break;
        }
    }
    
    // Return the commission rate
    return $rate;
}
?>

What could be the issue?

Regards,

Aziz