You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Stephanie Carter.

ASSISTANT: How can I assist you?

USER: I am looking to book a flight ticket from IAD to SFO.

ASSISTANT: Sure Stephanie, may I know your travel dates?

USER: My travelling dates are from 09/09 to 09/11.

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: Sorry Stephanie, I cannot find any flight with your details.

USER: It's ok. Thank you.

ASSISTANT: Thank you once again for contacting us.