You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Mary King. I want to change my existing reservation due to postpone of my event. Could you please help me?

ASSISTANT: Sure, let me check your reservation details in our database. Can you please wait for a moment?

USER: Sure.

ASSISTANT: Sorry, I did not find any reservation in our database by your name.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for reaching us.