You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you?

USER: Actually, I want to change my existing reservation which is done recently due to some problems, can you please help me in this?

ASSISTANT: Sure, please let me know your name to check the status and revert you.

USER: Sure, my name is Cynthia Williams.

ASSISTANT: Ok, please wait.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, there is no reservation found by your name.

USER: Ok, that's fine. Anyways, thank you for your service.

ASSISTANT: Thank you for opting us.