You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,.

USER: I am Margaret Walker.

ASSISTANT: How may I help you?

USER: We friends are planning to met after a long time at Chicago, can you please book me a flight ticket with single connection?

ASSISTANT: Ok. Please provide your travel dates.

USER: My planned dates are 02/07 and 02/09.

ASSISTANT: Could you please help me with travel codes.

USER: I would like to travel from DCA to ORD.

ASSISTANT: No flights found with your requirement.

USER: No issues, thank you for the information.

ASSISTANT: Thanks.