You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my reservation due to postponed of my exams, so please help me in changing.

ASSISTANT: Sure, may I know your good name?

USER: Sure, I am Linda Gonzalez from Washington.

ASSISTANT: Please wait for a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: No worries, thank you.

ASSISTANT: Thank you for reaching us.