You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I serve you today?

USER: I want to cancel my recent reservation due to some problem, can you please help me out?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: On which name do you reserved?

USER: Sure, my name is Donna Walker.

ASSISTANT: Donna Walker, there is no active reservation on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your service.