You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Charles Collins here.

ASSISTANT: How can I help you?

USER: Please help me out in booking the ticket from IAD to SEA.

ASSISTANT: Sure, please provide your travel dates.

USER: My departure and arrival dates will be Feb 7 to Feb 9.

ASSISTANT: Do you have any preferences?

USER: I want connected flight and depart time must be in the evening.

ASSISTANT: Sorry, we couldn't found any flights for you.

USER: That's ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you.