You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: I want to change my existing reservation. Can you help me for this one?

ASSISTANT: Yes, I will definitely try my best to help you in changing your existing reservation. Can you please share me your good name to check your reservation status?

USER: Sure, Michael Rodriguez here.

ASSISTANT: Ok, please wait for a while. I will check with it and get back to you soon.

USER: Sure.

ASSISTANT: Sorry for the inconvenience, we have not found any active reservation on your name in our database.

USER: No issues, thank you for the information.

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