Untitled

// Create list
$purchase_list = array(
    'post_title' => 'Name of the list',
    'post_status' => 'publish',
    'post_type' => 'b2bking_list',
    'post_author' => $customer_id,
);
$purchase_list_id = wp_insert_post($purchase_list);

// set list products and quantities
$listdetails = '209515:3|209517:1|209519:1|';
update_post_meta($purchase_list_id, 'b2bking_purchase_list_details', $listdetails);