You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my existing reservation due to misplace of journey dates.

ASSISTANT: Sure, I will help you. Can you please provide me your name?

USER: Helen Harris is my name.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok. Thank you for sharing the information.

ASSISTANT: Thanks for connecting with us, have a good day.