You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I have to change the trip dates because my friend is unable to travel now with us, so we have postponed the trip. Can you please help me to modify the details?

ASSISTANT: Sure, please share your good name?

USER: Thank you. My name is Jonathan Young.

ASSISTANT: Please wait for a while.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation found on your given name.

USER: It's ok, not a problem with that.

ASSISTANT: Thank you for choosing us.

USER: Anyhow thanks a lot for your time.