You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I would like to attend my nephew cradle ceremony at San Francisco with my relatives. Could you please help me with booking a plane ticket?

ASSISTANT: Sure, could you please share me with your dates of journey?

USER: Sure,  I intend to depart on Nov 30 and arrive on Dec 2.

ASSISTANT: Ok, may I know your respective airport codes of journey please?

USER: Sure, my source airport code is DFW and destination is SFO.

ASSISTANT: Do you need any other specifications please?

USER: Yes, I prefer to travel  in a business class.

ASSISTANT: Ok, please wait for a mean while.

USER: Sure, I will wait for your response.

ASSISTANT: May I know your good name please?

USER: I am Linda Evans.

ASSISTANT: Sorry Linda, there is no flight found as per your travelling details.

USER: No worries, thank you for the information.

ASSISTANT: You are welcome.