You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Steven Parker.

ASSISTANT: How may I aid you today?

USER: Can you please help me to modify my reservation as my exams got postponed?

ASSISTANT: Sure, please wait a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting. Sorry there are no active reservations to change.

USER: Not an issue, anyways thank you for the information.

ASSISTANT: Thank you for reaching our service.