You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Dorothy Smith.

ASSISTANT: How can I assist you?

USER: My examination scheduled dates has been postponed.So, I would like to change my recent reservation which is under my name. Can you please help me with that?

ASSISTANT:  Sure, can you please give me your planning dates? Sure, give me a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no reservation found.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for contacting us.

USER: You are welcome.