You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Donald Harris.

ASSISTANT: How can I aid you at this moment?

USER: I would like to change my recent reservation, can you help me to change that reservation?

ASSISTANT: Sure, I will help you with that.

USER: Sure, take your own time to check the reservation.

ASSISTANT: Ok. There is no previous reservation found under your name.

USER: That's fine, not a issue, thanks for your valuable information anyways.

ASSISTANT: Thank you for reaching us.