You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, May I know you name?

USER: I am Alexander Jackson.

ASSISTANT: How can I aid you at the moment?

USER: Due to an emergency, I need to change my existing reservation.

ASSISTANT: Sure, we are eager to help you.

USER: Ok.

ASSISTANT: Please hold on for a minute, I will revert to you.

USER: Sure.

ASSISTANT: Thanks for waiting, I really appreciate your patience. We did not find any reservation with the name of Alexander Jackson, in the reservation list.

USER: Thanks for the help.

ASSISTANT: Thank you for reaching us with a query. We hope to serve you again.

USER: Thanks.