You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you today?

USER: I would like to visit National Museum of Natural History located in Washington, could you please help me in booking a flight ticket?

ASSISTANT: Sure, may I know your price limit to search for the flight?

USER: Yes, my price limit is 5000.

ASSISTANT: Ok, could you please provide your airport codes?

USER: My origin airport code is ORD and my destination airport code is IAD.

ASSISTANT: Noted, kindly can you mention your dates of travel?

USER: I will be travelling from 01/18 to 01/20.

ASSISTANT: Ok, wait a moment please I will check the services in this route with your requirements.

USER: Ok, take your time.

ASSISTANT: Sorry to say, no flights were found with your requirements.

USER: No problem.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: My name is Barbara Walker. Thank you for your time.