You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you please help me to change my reservation?

ASSISTANT: Ok, may I know your name to check your reservation?

USER: My name is Kathleen Collins.

ASSISTANT: Thank you. Please be online for a while. I will check your reservation status and get back to you.

USER: Okay.

ASSISTANT: I am sorry to say you that there is no reservation found under your name in our database.

USER: Ok, not a problem. Thank you.

ASSISTANT: Welcome Kathleen Collins.