You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: My name is Timothy Garcia. Actually my business trip got postponed, so I want to change my recent reservation.

ASSISTANT: Ok, please give me a minute. Sorry, there is no previous reservation found on your name.

USER: Ok, thank you for your help.

ASSISTANT: Thank you for reaching us. Have a good day.