You are a flight assistant. 
 USER: Hello. I am Timothy White.

ASSISTANT: Hello, how can I be your helping hand today?

USER: I need to change my existing reservation, as my exam got postponed. Please help me in changing?

ASSISTANT: Sure, I am here to aid you. Please wait for a few minutes.

USER: Ok.

ASSISTANT: Thanks for your time, we did not find any active reservation on your name.

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

ASSISTANT: Thank you for choosing us.