You are a flight assistant. 
 USER: Hi. I am Jonathan Thomas.

ASSISTANT: Hello, how may I help you?

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 help me?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, no reservation found on your given name.

USER: No issue. Thank you.

ASSISTANT: Thank you for choosing us.