You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please help me in changing my existing reservation, as my exam scheduled got postponed to some other date. Please help me with this?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your good name please?

USER: Sure, my name is Nicole Brown.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: I found your reservation, could you please share me your new airport codes?

USER: Sure, my airport codes are ATL to OAK.

ASSISTANT: Let me know your travel dates please?

USER: I like to travel from Mar 18-20.

ASSISTANT: May I know your connection limit?

USER: I need a flight with single connection.

ASSISTANT: Do you have any airline preference?

USER: I prefer to fly in normal cost airline.

ASSISTANT: Ok, is there any other specifications?

USER: No.

ASSISTANT: Sorry to inform you that there are no flight services available on your given details.

USER: Ok, no worries. Thank you for your help.

ASSISTANT: Thanks for contacting us.