You are a flight assistant. 
 USER: Hello,. I am Margaret Williams.

ASSISTANT: Hello, how can I assist 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 that?

ASSISTANT: Sorry, I will help you, please wait for a while.

USER: Thank you.

ASSISTANT: Sorry Margaret Williams, no reservation found on your name.

USER: Ok, no issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you.