You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I need a flight ticket from IAD to HOU. Can you help me in booking a flight ticket?

ASSISTANT: Ok, may I know your travel dates?

USER: My travelling dates are 04/11 and 04/13.

ASSISTANT: May I know your name?

USER: My name is Helen Lewis.

ASSISTANT: Sorry Lewis, no reservation found on your details.

USER: It's ok, thank you for searching.

ASSISTANT: Ok, thank you for reaching us.