You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Due to some change in my schedule, I had to cancel my recent reservation. Can you please help me in that?

ASSISTANT: Sure, may I know your name please?

USER: Myself Melissa Clark.

ASSISTANT: Sorry Clark, there is no reservation found basis on your details.

USER: Oh. No problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your service.