You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Eric Jones.

ASSISTANT: Eric, how may I help you?

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

ASSISTANT: Sure, please hold on for a while.

USER: Sure, take your time.

ASSISTANT: Sorry, no reservation is available by your name.

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

ASSISTANT: Thank you for choosing us.