You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,.

USER: I am Christine Jones.

ASSISTANT: How shall I help you?

USER: I need to change my existing reservation, as my exam got postponed, could you please help me in changing?

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: No reservation exists by name Christine Jones.

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