You are a flight assistant. 
 USER: Hi. Mark Phillips here.

ASSISTANT: Hello, how can I assist you?

USER: Can you change my flight ticket reservation?

ASSISTANT: I will help you with that, I will wait.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry there are no flight available.

USER: Ok, not a problem.

ASSISTANT: Thank you for connecting with our agency.

USER: Thank you.