You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER:  Benjamin Collins here, due to sudden work so, I want to change my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait a minute.

USER: Ok.

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

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us, hope to serve you again.