You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hi. How can I help you?

USER: Cynthia Davis here. I wanted to change my reservation due to my planned program got postponed.

ASSISTANT: Sure, just a second please.

USER: Can you help me is there any chance to change my reservation. Sure.

ASSISTANT: I am sorry Cynthia Davis, I cannot find any reservation on your name.

USER: It's ok, no issues.

ASSISTANT: Thank you.

USER: Thanks for your helping me.