You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,.

USER: I am William Harris.

ASSISTANT: How can I aid you today?

USER: I just want to change my existing reservation, due to sudden demise of my grand mother. Can you please help me with it?

ASSISTANT: Sure, wait for sometime. I will check and get back to you.

USER: Thank you. OK.

ASSISTANT: Thanks for being patience, no reservation exists in your name.

USER: OK, not a problem. Thanks for your information.

ASSISTANT: Thanks for consulting us, have a nice day.