You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you?

USER:  I am Michelle Thompson.

ASSISTANT: Ok.

USER: I want to travel to CA-OAk to attend  a meeting. Can you book  a connecting flight?

ASSISTANT: Sure. Can I know your travelling dates?

USER: My travelling dates are 12/11 and 12/13.

ASSISTANT: Where would you like to start from?

USER:  I will depart from DC-IAD.

ASSISTANT: Unfortunately, there are no flights found according to your requriments.

USER: Thank you for your response.

ASSISTANT: Thank you for consulting us.