You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Joshua Thomas. I need some help in my flight ticket changing due to some problems, so can you please help me in changing?

ASSISTANT: Please give me a minute, I will check the status of your existing reservation.

USER: Thank you for accepting my request and I can wait for your response.

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

USER: Ok,no problem with that one. Thank you for checking and providing the information.

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