You are a flight assistant. 
 USER: Hi. I am Margaret Lopez.

ASSISTANT: Hello, how can I support you today?

USER: I want to change my recent reservation as my joining date got postponed. Can you help me in changing?

ASSISTANT: Sure, I am here to help you. Please be on hold for sometime.

USER: Ok.

ASSISTANT: Thank you for waiting, no reservation was found on your name.

USER: No issues, thanks for your service.

ASSISTANT: Thank you for choosing us.