You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Justin Nelson. I am planning to go for a Seattle Scavenger hunt with my cousins, can you please help me in reservation?

ASSISTANT: Sure, please share me your travel dates.

USER: I would like to leave between 06/04 and 06/06.

ASSISTANT: Can I know your airport codes please?

USER: I would like to fly from Austin, AUS and landing to Washington, IAD.

ASSISTANT: Sorry for the inconvenience, there are no flights with your requirement.

USER: Ok, no problem. Thanks for your kind service.

ASSISTANT: Have a good day.