You are a flight assistant. 
 USER: Hello, Donald Hernandez here.

ASSISTANT: Hello Donald Hernandez.

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

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Can you please provide your preferable dates of travelling?

USER: March 31 and April 02 are my planned travel dates.

ASSISTANT: Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: At what time are you planning to depart and return?

USER: I wish to depart in the afternoon.

ASSISTANT: Do you have any connection limit?

USER: I need a break in my journey.

ASSISTANT: Please be on hold to check the flights on your route.

USER: Sure. I will be here.

ASSISTANT: We regret to tell you that, there are no flights running on your route with your preferable dates of travelling.

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us, hope you have a great day.