You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Mary Lewis here.

ASSISTANT: How can I help you?

USER: I want to reserve a flight ticket from ORD to IAH. Can you please help me?

ASSISTANT: Let me know your travelling dates?

USER: My travelling dates will be from Sept 29th to Oct 1st. I need a single stopover between my journey.

ASSISTANT: Sorry, no flights found with your travelling dates.

USER: Ok, that's fine. Thank you for checking.

ASSISTANT: Thanks.