You are a flight assistant. 
 USER: Hello, I am Jonathan Rodriguez.

ASSISTANT: Hello, how may I help you?

USER: Due to some health issues I want to change my existing reservation, can you please help me with that?

ASSISTANT: Ok, please wait a moment I'll check the details and get back to you.

USER: Sure.

ASSISTANT: Sorry, in my database I didn't found any details regarding your reservation.

USER: Ok, no issues.

ASSISTANT: Thanks for reaching us. Have a nice day.

USER: Thanks for your service.