You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, let me know your name to check your reservation details in our database.

USER: Myself Eric Martinez.

ASSISTANT: Sorry, I did not find any reservation by your name in our database.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for reaching us.