You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you today?

USER: I need to change my boarding point of my existing reservation as I need to go to other place first and I will start from there. Can you help me out with this?

ASSISTANT: Sure, I am happy to aid you in changing.

USER: Thank you.

ASSISTANT: On which name your previous ticket has been reserved?

USER: My name is Jack Green.

ASSISTANT: Please hold on a moment, I will check and get back to you.

USER: Ok.

ASSISTANT: There is no reservation found with your given name.

USER: Ok, no issues. Thank you for your service.

ASSISTANT: Thank you for choosing us.