You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you help me to change my reservation which I had done last week?

ASSISTANT: Ok, may I know your name?

USER: Ok, please check for the name Justin Thompson.

ASSISTANT: Ok, please wait a minute.

USER: Ok, I will wait.

ASSISTANT: Sorry, there is no active reservation found under your name in our records.

USER: Ok, that is not a problem. Thank you for the information.

ASSISTANT: Most welcome.