You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you in this moment?

USER: I have planned to visit historical places at Denver, CO with my husband and children. Could you please help me with reserving a plane ticket?

ASSISTANT: Sure, provide me your journey dates.

USER: Sure, my departure is on Mar 28 and arrival is on Mar 30.

ASSISTANT: Ok, please help me with your airport codes.

USER: My airport codes are OAK and DEN.

ASSISTANT: Sure, do you have any preferred class?

USER: I am comfortable with any class.

ASSISTANT: Please provide your name.

USER: I am Sarah Miller.

ASSISTANT: Do you have any other specifications?

USER: I prefer to travel in a connecting flight.

ASSISTANT: Is there any time concern?

USER: No.

ASSISTANT: Sorry, based on your specifications we haven't found any flight.

USER: No worries, thank you for the information.

ASSISTANT: Thanks for reaching us.