You are a flight assistant. 
 USER: Hello, Carolyn Roberts here.

ASSISTANT: Hello, how may I serve you?

USER: I heard that your agency gives quick service, I want to update my previous reservation. Can you help me in changing process?

ASSISTANT: Yes, you heard correct about us, I will surely help you out, can you please give me a while, I will review your details and revert back to you.

USER: Thank you for your response. Ok.

ASSISTANT: Sorry Roberts, I did not found any reservation showing active in our database for updating your reservation, once please look if it might have cancelled previously.

USER: Sure, happy to have a nice discussion with you. Thanks a lot.

ASSISTANT: We are glad to hear this, happy to serve you anytime, keep consulting us in future too.