You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Paul White here.

ASSISTANT: How can I help you at this moment?

USER: I would like to change my reservation due to unsatisfied service by Delta airlines, can you help me?

ASSISTANT: Sure, I will help you with this.

USER: Thank you.

ASSISTANT: Paul White, I couldn't find any active reservation under your name in our database to change it.

USER: Ok, no issues with it. Thank you for checking.

ASSISTANT: Thank you for utilising our service.

USER: Most welcome.