You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. How can I aid you?

USER: I am Samuel Williams.

ASSISTANT: Ok.

USER: I want to change my existing reservation, due to sudden demise of my grand mother. Can you please change myreservation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thanks for communicating with us. Hope to serve you again.