You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Jonathan Moore and I would like to change an existing  reservation. Can  you help me?

ASSISTANT: Sure, I am here to help you for this. May I know your name please?

USER: Jonathan Moore.

ASSISTANT: Just a moment, let me check your reservation status in our database.

USER: Sure, take your time.

ASSISTANT: Sorry for inconvenience, no reservation is found with your criteria.

USER: No issue. Thank you for the information.

ASSISTANT: Thank you very much for approaching our agency.