You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jack Collins.

ASSISTANT: How can I help you?

USER: I want to change my existing reservation due to sudden demise of my grandfather. Can you please help me with this?

ASSISTANT: Let me check the reservation status.

USER: Sure.

ASSISTANT: Sorry, no reservation found by your name.

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

ASSISTANT: Thank you.