You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you?

USER: I want to meet my grand parents who are staying in DCA. So, can you please help me to book a flight from SEA?

ASSISTANT: Sure, I am glad to assist you with the booking.

USER: Thank you.

ASSISTANT: May I know when are you planning to start from Seattle?

USER: Sure, I want to start my journey on Jan 21 and need to end it on Jan 23.

ASSISTANT: Ok, do you desire any particular time to depart and return?

USER: No.

ASSISTANT: May I know if you prefer any specific airline?

USER: I prefer to travel in an normal-cost airline.

ASSISTANT: Sure, which class do you like to travel?

USER: I am comfortable with any class.

ASSISTANT: Is a connecting flight works for you?

USER: Yes, please proceed.

ASSISTANT: Do you have any other preference?

USER: No.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, we didn't find any flight which meets all your requirement.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for reaching us, we hope to serve you better next time. May I know your name for documentation purpose?

USER: My name is Jennifer Wright.

ASSISTANT: Thank you.

USER: Thank you.