You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Helen Gonzalez here.

ASSISTANT: How may I aid you today?

USER: I want to cancel my reservation due to my health issue.

ASSISTANT: Sure, I will help you in cancelling the reservation.

USER: Thank you for noting my request.

ASSISTANT: Please wait for a while.

USER: Ok, sure please take your time.

ASSISTANT: Sorry, there are no reservations available to cancel your ticket.

USER: It's ok, anyway thank you for the information.

ASSISTANT: Thank you for choosing us.