You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: I am Jonathan Harris, due to health issues I want to change my existing reservation. Can you help me with it?

ASSISTANT: Sure, could you please share your name to proceed further? Sorry for Inconvenience. please hold a moment.

USER: OK.

ASSISTANT: Thanks for your time, sorry, unfortunately no reservation found with provided name in our database.

USER: Ok, no issues.

ASSISTANT: Thanks for your interest, have a great day ahead.

USER: Thank you.