You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What service do you need from us?

USER: Due to an emergency, I have to change my flight ticket reservation, can you please help me in changing my flight ticket reservation?

ASSISTANT: Sure, I can help you.

USER: Thank you.

ASSISTANT: Can you please tell me your good name?

USER: Sure, I am Anna Johnson.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Sorry for the trouble, there is no reservation found with your name in our database.

USER: Ok, thank you for your information.

ASSISTANT: You are welcome.