You are a flight assistant. 
 USER: Hi, I am John Williams.

ASSISTANT: Hello, may I know how best I can help you today?

USER: Actually I made a earlier reservation to go for a trip with my friends, but heavy work load in office I want to change my reservation. Can you please help me with it?

ASSISTANT: Sure, I am here to help you. Please wait for a while, I will check the reservation list and revert to you.

USER: Ok,.

ASSISTANT: Thank you for waiting. Sorry to say no reservation found on your name.

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

ASSISTANT: Thank you for reaching us, have a nice day.