You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I have to change my reservation because my trip is postponed, can you please change my reservation?

ASSISTANT: Sure, I am ready to help you with that. Can I have your name please for checking your reservation status?

USER: Thank you. My name is Anna Hernandez.

ASSISTANT: Ok, please wait a moment to check your reservation status.

USER: Sure.

ASSISTANT: Sorry Anna Hernandez, no reservation has found under your name to change.

USER: Not an issue, anyway thank you very much for checking.

ASSISTANT: Thank you for choosing us, have a good day.