You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you now?

USER: Due to an emergency, I want to change my reservation. Can you help me?

ASSISTANT: Ok, please mention your name to check with your previous booking.

USER: Mary Lewis here.

ASSISTANT: Mary Lewis, no reservation was found by your name.

USER: No issue, Thanks for the information.

ASSISTANT: Thank you for choosing our airlines for your help.