You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I would like to visit Mt rainer tour, with my friends.So,please book a flight to Seattle, SEA.

ASSISTANT: Ok, may I know your travel dates?

USER: My plan is to start on 04/11 and arrive on 04/13.

ASSISTANT: Ok, may I know your source point?

USER: Austin,AUS is nearest airport to my home.

ASSISTANT: Sorry, no flights are available on your requested  dates.

USER: Ok, Thanks for your information. I am glad at your quick response.

ASSISTANT: Thank you for availing us.