You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Karen Gonzalez want to change my reservation due to prepone of my meeting with clients. Can you help me in changing?

ASSISTANT: Sure, we are here to help you. Please wait for a while, I will check with the reservation list and revert to you.

USER: Ok.

ASSISTANT: Thank you for being patient, No reservation found on your given name.

USER: Ok, thank you for your help.

ASSISTANT: Thank you for availing us.