You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you now?

USER: I want to change my flight reservation as I am sick, can you please help me to change my reservation?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please mention your good name?

USER: I am Samantha Thomas.

ASSISTANT: Please wait for a moment, while I check for the reservation.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: Sad to hear that, thank you for checking.

ASSISTANT: Thank you for visiting us, we hope see you again.