You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I need a direct flight to submit tender in Washington, can you please help me in reservation process?

ASSISTANT: Sure, may I know your trip dates?

USER: My journey start on Dec 2nd, and arrival on Dec 4th.

ASSISTANT: Help me with the airport codes?

USER: My airport codes are, SEA to IAD.

ASSISTANT: May I know your name please?

USER: My name is Donna Anderson.

ASSISTANT: Sorry, no flights were available at this moment.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.