You can handle that via your stories. If there are multiple orders, you could set the slot multiple_orders to true in your action action_num_of_orders. In your stories you can then do
# story 1: just one order
- action_num_of_orders
- slot{"multiple_orders": false}
- action_whatever_else
# story 2: multiple orders
- action_num_of_orders
- slot{"multiple_orders": true}
* enter_order_id
- action_get_order_id
- action_whatever_else
So depending on the slot value, a different action would be picked after action_num_of_orders. Does that help?