You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you out?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me?

ASSISTANT: Sure, I will help you in changing the ticket. May I know your name please?

USER: Sure, my name is Stephanie Anderson.

ASSISTANT: Sorry, there are no reservations found in our database.

USER: Ok, not an issue.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your service.