You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I oblige you today?

USER: My exams got postponed so, I want to change my reservation to revised dates. Can you please help me in changing the reservation?

ASSISTANT: Sure, may I have your name please?

USER: I am Christopher Hernandez.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: Thanks for waiting, no reservation found on your name.

USER: Ok, no issues. Thank you for your quick response.

ASSISTANT: Thank you for choosing us.