You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I support you today?

USER: I need to change my reservation due to urgent meeting, can you help me?

ASSISTANT: Sure, I am here to help you. Can you please mention your name to check further in our database?

USER: I am Betty Hill.

ASSISTANT: Please stand by.

USER: Sure.

ASSISTANT: Sorry, no reservation found with your given name in our database to change it.

USER: That's ok. Thank you for your help.

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