You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me in this?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your name to check your previous reservation status?

USER: Sure, my name is Gregory Brown.

ASSISTANT: Ok, please be on hold.

USER: Sure, I will wait.

ASSISTANT: Sorry, there is no reservation found on your name in our records.

USER: Ok, not an issue. Anyways, thank you for your service..

ASSISTANT: Thank you for reaching us.