You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my reservation due to my bad health. Can you help me?

ASSISTANT: Sure, I will help you. Please let me know your name.

USER: My name is Patricia Miller.

ASSISTANT: Thank you. Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

USER: Ok, thank you for the information.

ASSISTANT: You are welcome and thank you for choosing us.