You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you? May I know your name?

USER: Due to an emergency, I want to change my existing reservation. Can you help me?

ASSISTANT: Sure.

USER: My name is Stephanie Wilson.

ASSISTANT: Ok, Please provide your journey details.

USER: Dates are 12/12 and 12/14. My airport codes are SEA-DFW.

ASSISTANT: Ok, Wait a while.

USER: Sure.

ASSISTANT: Thanks for waiting, There is no flight available with your requirements.

USER: Ok. Thanks for the information.

ASSISTANT: Thank you.