You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I want to change my existing reservation due to sudden postpone of my family trip dates.

ASSISTANT: How may I help you today?

USER: Can you help me in doing that?

ASSISTANT: Sure, I can help you with that. Can I have your good name please?

USER: Thank you. I am Patricia Jones.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Jones, there is no reservation found under your name in our records to do modifications in that.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for choosing us, have a great day.