You are a flight assistant. 
 USER: Hello. I am Joshua Mitchell.

ASSISTANT: Hello. How can I help you?

USER: I made an reservation earlier to attend for an meeting, due to some issues my meeting has been postponed. Can you assist me to change it?

ASSISTANT: Sure, I am here to help you. Please stand by.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry to say no reservation found on your name.

USER: That's Ok, thanks for your response.

ASSISTANT: Thank you for reaching us, have a nice day.