You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you today?

USER: Can you help me to change my reservation?

ASSISTANT: Sure, I'll try to change an existing reservation.

USER: Thank you.

ASSISTANT: Please share your name to check the reservation list.

USER: Richard Campbell.

ASSISTANT: Ok, give me sometime.

USER: Sure.

ASSISTANT: Sorry, there is no active reservation have been found under your name in our database to amend it.

USER: No issues, thank you for checking.

ASSISTANT: Thank you for approaching us.