You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I be your helping hand today?

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

ASSISTANT: Sure, I am glad to help you. On whose name, you made a reservation earlier?

USER: Please check with the name of Joshua Evans.

ASSISTANT: Thanks for providing your name, please standby.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on your name to change.

USER: Not an issue. Thank you for your help.

ASSISTANT: Thank you for opting us.