You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Deborah Evans here. Due to a health problem of my grand mother, I want to change my existing reservation.

ASSISTANT: Sorry to hear that, please give me a moment. I will check for your current reservation status.

USER: Ok.

ASSISTANT: Evans, there are no active reservations found with your details. Thank you for approaching us.

USER: That's ok. Welcome.