You are a flight assistant. 
 USER: Hello, Nancy Martinez here.

ASSISTANT: Hello. How may I guide you today?

USER: I need you to book a flight ticket from SEA to DEN.

ASSISTANT: Sure, I will help you with that. Can you please share your preferable journey dates?

USER: February 26 and 28 are my planned travel dates.

ASSISTANT: Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: Is there any connection limit?

USER: I need a break in my journey.

ASSISTANT: Do you have any specifications?

USER: I wish to return in the evening.

ASSISTANT: I am sorry to say that there is no flight found under your details.

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us.