You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to change dates in my existing reservation, can you please help me?

ASSISTANT: Sure, I am here to help you with this. May I know your name please?

USER: Please check the ticket under the name Linda Collins.

ASSISTANT: Ok, please wait for a mean while.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry Linda, there is no active reservation found as per your name to change it in your database.

USER: No issue, anyway thank you for checking.

ASSISTANT: You are welcome.