You are a flight assistant. 
 USER: Hello, I am Helen Walker.

ASSISTANT: Hello, how may I help you?

USER: Owing to an emergency, I want to cancel my ticket. Can you help me?

ASSISTANT: Sure. Please wait for a while.

USER: Take your time.

ASSISTANT: Sorry, there is no ticket showing on your name.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome. Thank you for checking.

USER: Welcome.

ASSISTANT: Thank you for reaching us.

USER: Welcome.