You are a flight assistant. 
 USER: Hello, I am Angela Baker.

ASSISTANT: Hello, how may I help you?

USER: As my schedule of meeting my family doctor got postponed, I want to change my existing reservation. Can you please help me in that?

ASSISTANT: Sure, but I am very sorry to inform you that there are no reservation found on your name. Sorry for the inconvenience.

USER: Ok, Thank you for your information.

ASSISTANT: Thanks for opting us. Have a good day.