// Restricted Customer issue
add_filter( 'wcfm_is_component_for_vendor', function( $is_component_for_vendor, $component_id, $component, $current_vendor ) {
    if ( 'customer' != $component ) return $is_component_for_vendor;

    global $wpdb;

    $sql = $wpdb->prepare(
        "SELECT `order_id` FROM {$wpdb->prefix}wcfm_marketplace_orders WHERE `vendor_id`=%d AND `customer_id`=%d",
        $current_vendor,
        $component_id
    );
    $has_orders = $wpdb->get_results( $sql );

    if ( is_array( $has_orders ) && !empty( $has_orders ) ) $is_component_for_vendor = true;

    return $is_component_for_vendor;
}, 10, 4);