You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I want to change my travelling dates in my previous ticket because the trip got postponed. Can you help me in altering my ticket details?

ASSISTANT: I am happy to help you, can you please tell me your name?

USER: My name in the previous ticket is Nancy Hernandez. So please check with that.

ASSISTANT: Please wait, let me check your reservation status.

USER: Sure, I will wait for your reply.

ASSISTANT: Nancy, I have not found any reservation by your name.

USER: Oh! It's ok, thank you for checking.

ASSISTANT: Thank you for contacting us and have a nice day.

USER: You are welcome.