You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I render you today?

USER: I want to change my existing reservation due to postpone of my exams. Can you help me in that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Could you please provide your name to check the previous reservation status?

USER: Myself Jacob Clark.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for opting us.