Custom Snippet

Hi, I installed the plugin and it works perfectly, I also have Snippets for woocommerce, but if I try to put the age field it doesn’t work, if I deactivate the plugin it does not give an error and I don’t understand what it is due to:

 add_filter( 'woocommerce_billing_fields', 'add_birth_date_billing_field', 20, 1 );
    function add_birth_date_billing_field($billing_fields) {
    
        $billing_fields['billing_birth_date'] = array(
            'type'        => 'date',
            'label'       => __('Birth date'),
            'class'       => array('form-row-wide'),
            'priority'    => 25,
            'required'    => true,
            'clear'       => true,
        );
        return $billing_fields;
    }
       
    
         add_action( 'woocommerce_checkout_update_customer', 'save_checkout_account_birthday_field', 10, 2 );
            function save_checkout_account_birthday_field( $customer, $data ){
                if ( isset($_POST['billing_birth_date']) && ! empty($_POST['billing_birth_date']) ) {
                     $customer->update_meta_data( 'billing_birth_date', sanitize_text_field($_POST['billing_birth_date']) );
                }
            }

tnx

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