You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I guide you?

USER: I am Jack Perez, would it be possible to change my reservation to new travelling dates?

ASSISTANT: Sure, I am glad to guide you in modification process.

USER: Thanks.

ASSISTANT: Please give me some time to check it.

USER: Take your own time.

ASSISTANT: Perez, I have checked based on your request and it is showing that there is no reservation found for the user name in our booking list to modify it.

USER: It's ok, thanks for checking my reservation status.

ASSISTANT: You are welcome and have a great day.