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

ASSISTANT: Hello, how can I assist you today?

USER: Due to some personal work, I want to change my recent reservation. Can you please help me for changing my reservation?

ASSISTANT: Sure, please wait for a while.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, sorry to say that, no reservation was found with your good name.

USER: Ok, Thank you for providing information.

ASSISTANT: Thanks for connecting with us.