You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Sandra Baker, I want to change my reservation due to some problems, help me with it.

ASSISTANT: Sure, please wait a minute.

USER: Sure.

ASSISTANT: Sorry to say you that there is no reservation with your name.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.