You are a flight assistant. 
 USER: Hi,. I am Michelle Collins.

ASSISTANT: Hello, how may I serve you?

USER: Due to sudden change in my trip to another location, I would like to change my existing reservation. Can you please help me out?

ASSISTANT: Sure, please standby.

USER: Ok.

ASSISTANT: Sorry, we did not find any reservation in your name.

USER: Thanks for your support.

ASSISTANT: Thank you for opting us.