You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you for today?

USER: Myself William Thompson from Washington. I want to change my travel dates in my previous reservation. Can you please help me with that?

ASSISTANT: Sure, I will help you with that Thompson.

USER: Thank you for your positive response.

ASSISTANT: Please wait for sometime, while I will check the reservation status with your name.

USER: Ok.

ASSISTANT: I regret to say this Thompson, there are no reservations with your name in our data base.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: You are welcome, thank you for reaching out here. Hope you have a nice day ahead.