You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know your name?

USER: Rebecca Scott here.

ASSISTANT: How may I help you?

USER: I wanted to change my reservation due to my planned program got postponed. Can you help me is there any chance to change my reservation?

ASSISTANT: Ok, wait a moment.

USER: Sure.

ASSISTANT: Unfortunately, no reservation found your information.

USER: It's ok, no issues. Thank you.

ASSISTANT: Thank you for choosing us, have a nice day.