You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How can I assist you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: Can I know your name please?

USER: Thank you, myself Amy Collins.

ASSISTANT: Please wait. Sorry, no reservation found on your name to change.

USER: Ok. Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your help.