You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,how may I help you?

USER: I want to travel in a flight and trying to book a flight from ORD to DTW.

ASSISTANT: OK, may I know your name please?

USER: My name is Sandra Green.

ASSISTANT: OK Sandra,can I know your travelling dates?

USER: Sure, I want to travel on these dates that is from 05/27 to 05/29.

ASSISTANT: I am sorry Sandra,there is no flight found based on your details.

USER: It's OK.

ASSISTANT: Thank you for contacting us.

USER: Thank you.