You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: Can you change my reservation to new dates which I have done with my name Steven Thomas.

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait a moment to check your previous reservation.

USER: Sure, get back with the status.

ASSISTANT: Sorry to inform you that, there is no reservation found with your name in our records.

USER: It's ok, no issues. Anyway thanks for your information.

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