You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I  want to cancel my recent reservation due to postpone of my exams, can you help me?

ASSISTANT: Sure, may I have your name please?

USER: I am Melissa Lopez.

ASSISTANT: Ok, please hold on.

USER: Sure.

ASSISTANT: Thanks for your time, no reservation was found on your name.

USER: No issues. Thank you for your service.

ASSISTANT: Thank you for choosing us.