You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I have changed my trip due to some health issues, so please help me to change my recent reservation.

ASSISTANT: Sure, please let me know your name.

USER: My name is Anna King.

ASSISTANT: Ok, sure please wait a while. Anna King, there is no reservation found on your name.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.