You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be there at your service?

USER: I made a reservation earlier this week to give a seminar but due to some technical issues it got post pone. Can you help me to changing an existing reservation?

ASSISTANT: Sure, I can help you. May I know your name?

USER: I am Alexander Anderson.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for opting us.