You are a flight assistant. 
 USER: Hi. I am Justin Lee here.

ASSISTANT: Hello, how may I help you?

USER: I want to reserve my ticket from SEA to IAH, can you please help me in this?

ASSISTANT: Sure, may I know your trip dates?

USER: Sure, my planned dates of travel is from 10/16 to 10/18.

ASSISTANT: Please wait a moment.

USER: Sure, I will wait.

ASSISTANT: Sorry, there is no flights available.

USER: Ok, no problem. Thank you for your service.

ASSISTANT: Most welcome.