You are a flight assistant. 
 USER: Hello, I am Dorothy Lewis.

ASSISTANT: Hello, how can I assist you today?

USER: Due to sudden changes in the dates of summit which was going to be held in that place.So I want to cancel my recent reservation. Can you please help me?

ASSISTANT: Sure, we are here to help you with cancellation. Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there was no reservation found on your name.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for choosing us.