You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Carolyn Martinez.

ASSISTANT: How may I assist you?

USER: I want to alter my reservation, due to postponement of concert to be held at the place where I wanted to visit, can you please take your some time for helping me?

ASSISTANT: Sure, I will help you with that.

USER: Ok.

ASSISTANT: Martinez, there is no reservation found for you to change.

USER: No problem, thank you for checking.

ASSISTANT: You are welcome. Thank you for choosing us.