You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I am Thomas Walker, would it be possible to change my reservation to new travel dates?

ASSISTANT: Yes, please wait for a moment. I will check and get back to you.

USER: Sure, take your own time.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for reaching us.