You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Sure, can you share your name for checking?

USER: I am William Smith.

ASSISTANT: Give me a minute.

USER: Sure.

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

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

ASSISTANT: Thank you for reaching us.