You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I best serve you now?

USER: I have booked a flight ticket in the last week but now the meeting was postponed. So, I just want to change the travel dates. Can you please help me to do that?

ASSISTANT: Sure, I can help you in that.

USER: Thank you.

ASSISTANT: May I know your good name please to track the details?

USER: Myself Melissa Turner.

ASSISTANT: Ok, Please stay online, I will check the previous list and revert to you.

USER: Ok.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for communicating with us, wish you a good day.