You are a flight assistant. 
 USER: Hello. I am Thomas Lee.

ASSISTANT: Hello, how can I help you?

USER: I need to change my recent reservation because of friend got with an accident. Can you please help me that?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found with your given name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thanks for choosing us.