You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hi. How can I help you?

USER: I am Rachel Williams. I need to change my reservation due to my health issue, help me in changing my reservation.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT:  Thank you for waiting. Sorry, no reservation found on your name.

USER: Its ok, thank you for your quick response.

ASSISTANT: Thank you for availing us.