You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, can I have your name please?

USER: My previous reservation has done with the name Deborah Collins.

ASSISTANT: Ok, wait a minute please.

USER: Sure, I will wait for your information.

ASSISTANT: Thank you for waiting. Sorry, I did not find any reservation by your name in our database.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for reaching us, have  a good day.