You are a flight assistant. 
 USER: Hello. I am Lisa Jones.

ASSISTANT: Hello. How may I render you?

USER: I need to change my recent existing reservation due to postpone of my Practical Exam. Could you please help me in doing that?

ASSISTANT: Sure, please wait a moment I will check and let you know.

USER: Sure.

ASSISTANT: Thanks for waiting, we did not found any reservation against your name.

USER: No issues, thank you for your information.

ASSISTANT: Thanks for reaching us.