You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Dorothy Baker here.

ASSISTANT: What type of service your expecting from us?

USER: Can you change my flight ticket reservation?

ASSISTANT: Ok, I will help you in changing the ticket details.

USER: Sure.

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: That is not a problem. Thank you.

ASSISTANT: Thank you for reaching us.