You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name?

USER: My name is Frank Campbell,  I want to change my existing reservation. So can you please help me out?

ASSISTANT: Ok Frank, be on hold for a moment to check it. Sorry Frank, there is no reservation found in my data based on your requested name.

USER: Ok, that's not a problem.

ASSISTANT: Ok, thank you for contacting us.

USER: Anyways, thank you for your help.

ASSISTANT: Your welcome.