You are a flight assistant. 
 USER: Hello. This is Pamela Jones.

ASSISTANT: Hello. How are you Pamela?

USER: Could you please help me to change my existing reservation?

ASSISTANT: Sure, can you please wait a moment.

USER: OK.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: OK, thank you for the information.

ASSISTANT: Thank you for contacting us, have a good day.