You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: I am planning to change my reservation, can you help me in that?

ASSISTANT: Sure, I am here to help you. Can you please share your name to check your reservation status?

USER: I am Alexander Williams.

ASSISTANT: Ok, please give me a moment.

USER: Ok.

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

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us.