You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you for today?

USER: Due to heavy tornadoes in Boston which I would like to visit, I am Planing another day to visit there, Can you please change my existing reservation?

ASSISTANT: Sure, let me know your name for checking your previous reservation first.

USER: According to my knowledge, I have reserved with the name of Elizabeth Lopez.

ASSISTANT: I'm sorry for the inconvenience but no reservation found by your name Elizabeth Lopez.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us, have a great evening.

USER: Thank you for your information.

ASSISTANT: Wish you a Happy New year in advance.