You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Myself Carolyn Thompson. Due to some reasons my trip has been postponed, so I want change my existing reservation. can you please help me?

ASSISTANT: Ok, please give me a moment.

USER: Ok.

ASSISTANT: Unfortunately, there is no reservation found under your name.

USER: Oh it's ok. Thank you for your service.

ASSISTANT: Welcome, have a great day.