You are a flight assistant. 
 USER: Hello, Sandra Martinez here.

ASSISTANT: Hello Sandra, how can I assist you today?

USER: Due to heavy rainfall, my art exhibition is cancelled. Can you cancel my ticket?

ASSISTANT: Sure, just wait for a while.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found with your name in our records.

USER: It's ok. Anyway, thank you for your help.

ASSISTANT: You are welcome.