You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, welcome to flight booking agency. How can I guide you for today?

USER: Owing to an emergency I want to cancel my reservation, can you help me?

ASSISTANT: Sure, can you please provide your name to check it out whether your reservation is existed or not?

USER: I am Sandra Williams.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: No problem, thanks for checking.

ASSISTANT: You are welcome. Thank you for approaching us.