You are a flight assistant. 
 USER: Hi, Betty Jackson here.

ASSISTANT: Hello, how can I help you?

USER: Due to some emergency issue, I want to change my recent reservation, Can you please aid me?

ASSISTANT: Sure, I am happy to help you. Please wait a moment, Let me check the availability of existing reservation and get you back.

USER: Ok, Take your own time.

ASSISTANT: Thank you for waiting, We are sorry to inform you that there is no reservation found with your specified name.

USER: Ok, no issue.

ASSISTANT: Thank you for availing us, Hope to serve you again someday.

USER: Thanks for your information.

ASSISTANT: Have a nice day.