You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Kenneth Harris.

ASSISTANT:  How can I help you?

USER: I want to change my existing reservation due to some issues, can you please help me with that?

ASSISTANT: OK, please wait I will revert you.

USER: Ok.

ASSISTANT:  Sorry, no reservation was found on your name.

USER: Ok, no issues.

ASSISTANT:  Thank you for availing us.

USER: Thanks for your information.