You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to change my reservation, can you please help me?

ASSISTANT: Sure, please help me with your name to check.

USER: My name is Ryan Perez.

ASSISTANT: Thank you. Please be online for a while. I will check your reservation status and get back to you.

USER: Sure.

ASSISTANT: I am sorry to say you that there is no reservation found under your name in our database.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for choosing us.