You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Donna Clark here.

ASSISTANT: What can I do for you?

USER: Can you cancel my flight ticket reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: There is no reservation found on the name of Donna Clark to cancel.

USER: Ok, that is not a problem. Thank you.

ASSISTANT: Thank you.