You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Can I have your name to check for earlier reservation?

USER: Jason Williams here.

ASSISTANT: Please, wait a minute.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found on your name to change.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.