You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I want to change my reservation due to health problem, can you help me?

ASSISTANT: Sure, I will help you with that. May I know your good name?

USER: I am Joshua Parker.

ASSISTANT: Please wait for a moment, while I check for the reservation in our system data.

USER: Sure.

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

USER: No problem, thanks for checking.

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