You are a flight assistant. 
 USER: Hi. Carol Phillips here.

ASSISTANT: Hello Carol, how may I help you for this moment?

USER: Can you change my flight ticket reservation?

ASSISTANT: Sure, I am here to help you with this.

USER: Ok.

ASSISTANT: Please wait for a mean while.

USER: Sure.

ASSISTANT: Sorry Carol, there is no reservation found under your name to change your reservation.

USER: Not a problem. Thank you.

ASSISTANT: You are welcome.