You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I would like to shift my planned dates to some other dates, please help me in changing my existing reservation.

ASSISTANT: Sure, may I know your good name please?

USER: My name is Rebecca Miller.

ASSISTANT: Wait a minute.

USER: Sure, take your time.

ASSISTANT: Sorry, there was no reservation found on your name.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for reaching us.