You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Timothy Thomas.

ASSISTANT: Thomas, how can I assist you today?

USER: I need modify my reservation, can you help me out please?

ASSISTANT: Sure, I will help you in changing your reservation. I will check your reservation status and get back to you.

USER: Ok.

ASSISTANT: Thomas, I have not found any reservation by your name in our database.

USER: That's ok, no problem. Thank you for your help.

ASSISTANT: Thank you for contacting us and have a nice day.