You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Dennis Thomas.

ASSISTANT: How may I help you?

USER: My holiday trip has been postponed. So, I would like to change my reservation. Can you please help me with that?

ASSISTANT: Ok, please hold on a moment, I will let you know the reservation status of your's.

USER: Sure, take your time.

ASSISTANT: Thanks for your time, there is no reservation found with your name.

USER: Ok, no issues, Thank you for checking.

ASSISTANT: Welcome, have a nice day.