You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you now?

USER: Myself Timothy Williams. I need to change my existing reservation, can you please help me?

ASSISTANT: Sure, I will help you with that. Please wait for a while.

USER: Thank you for your kind reply.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name.

USER: That's ok, thank you for searching the details.

ASSISTANT: Thank you for reaching us.