You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Myself Sandra Clark.

ASSISTANT: Good to know you, Sandra.

USER: I want to change my reservation, can you please help me out?

ASSISTANT: Sure, please give me a minute.

USER: Sure.

ASSISTANT: No reservation found for you, Sandra.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for choosing us. Have a nice day.