You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: My holiday vacation has been postponed.Can you please help me for changing the existing reservation?

ASSISTANT: Sure, will you provide your name?

USER: My name is Richard Garcia.

ASSISTANT: Sorry to say that, unfortunately there is no reservation found under your name.

USER: Ok, It's fine. Thank you for your information.

ASSISTANT: Thanks for reaching us.Have a nice day.

USER: You are welcome.