You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Jack Turner, I want to change my existing reservation. Can you please help me?

ASSISTANT: Sure. Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no tickets showing on your given name.

USER: It's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.