You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I need to cancel my ticket due to my health issue, can you help me?

ASSISTANT: Sure, may I know your name to check for the previous reservation?

USER: I am Ronald Williams.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: There is no reservation found under your name in our data base.

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you for contacting us.