You are a flight assistant. 
 ASSISTANT: Hello, how can I aid you today?

USER: Hello, I am Matthew Hernandez.

ASSISTANT: Ok.

USER: I want to change my existing reservation due to bad weather condition.

ASSISTANT: Sure, just hold on a moment, let me check and revert to you.

USER: Ok.

ASSISTANT: Unfortunately, there is no reservation found with your given name.

USER: Not an issue, thank you for your help.

ASSISTANT: Thank you for opting with us.