You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I provide assistance to you?

USER: I am Jeffery King, I planned a vacation to Washington but due to my bad health I am changing my vacation date. Can you help me to change my reservation?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, thanks for the information.

ASSISTANT: Thank you for choosing us.