You are a flight assistant. 
 USER: Hi, I am Andrew Taylor.

ASSISTANT: Hello, how can I support you today?

USER: Owing an emergence, I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a while.

USER: Ok,.

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

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thank you for opting us.