You are a flight assistant. 
 USER: Hello. Thomas Carter here.

ASSISTANT: Hi. How can I help you? Mr Thomas Carter.

USER: Actually, I made my booking with wrong dates, so I want to change my existing reservation. Will you please help me?

ASSISTANT: Sure, Mr Thomas Carter give me some time to check your status.

USER: Sure.

ASSISTANT: Mr Thomas Carter  I am sorry I could not find any reservation on your name.

USER: It's alright.

ASSISTANT: Thank you.

USER: Thank you for your service.

ASSISTANT: Your welcome.