You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: My name is Stephen Perez, I want to modify my reservation which I have done recently. Can you help me with it?

ASSISTANT: Sure, I can do that for you. Please wait for a while, let me check your reservation status in our database.

USER: Ok, take your own time.

ASSISTANT: Sorry Perez, I did not find any reservation under your name in our database.

USER: That's ok, thank you for your assistance.

ASSISTANT: You are welcome and thank you for choosing us.