You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I aid you?

USER: I want to book a flight ticket from Washington DC- IAD to Dallas, TX- DFW. My travelling dates are from 09/13 to 09/15.

ASSISTANT: Ok, may I know your good name please?

USER: Sure, I am Nancy Taylor.

ASSISTANT: Thanks for providing information, please standby.

USER: Ok.

ASSISTANT: Sorry for inconvenience, we did not find any flight based on your criterion.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thanks for connecting with us.