You are a flight assistant. 
 USER: Hi. My name is Joshua Rodriguez.

ASSISTANT: Hello, How can I assist you today?

USER: I want to change my existing reservation due to Beer festival got postponed. Can you help me with change reservation?

ASSISTANT: Ok, please wait a moment, I will check with reservation list.

USER: Sure.

ASSISTANT: Thanks for being patience, unfortunately we could not find your name in the list to change.

USER: Ok, No problem.

ASSISTANT: Thanks for availing us, Have a great day.

USER: Thanks for the information.