You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: My scheduled examination dates has been postponed, could you please help me with changing my recent reservation?

ASSISTANT: May I know your name please?

USER: My reservation was done under the name Donna Walker.

ASSISTANT: Please wait for a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation found basis on your details.

USER: That's ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for reaching us.