You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: Can you please book a flight ticket from DCA to SFO for my business trip?

ASSISTANT: Please mention your travelling dates?

USER: Thank you, my boarding is on Oct 29 and please book my return ticket on Oct 31.

ASSISTANT: Is there any connection limit?

USER: Yes, I will prefer single connection.

ASSISTANT: Can you please help me with your good name?

USER: Sure, my name is Kevin Edwards.

ASSISTANT: Do you have any other requirements?

USER: I would like to return in afternoon time.

ASSISTANT: There are no flights found with your required dates to travel.

USER: Oh! Sad to hear that. Anyway, I will find another alternative. Thank you for the information.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.