You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I want to change my recent reservation. Can you help me out?

ASSISTANT: I will assist you with that, may I know your name please?

USER: I am Nicholas Williams.

ASSISTANT: Wait a moment please.

USER: Ok, take your time. That's ok. Anyways, thank you.

ASSISTANT: Nicholas Williams, we haven' found any reservation under your name in our database. Thank you for reaching us.