You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my reservation, due to some problems I am not unable to travel those dates, can you please help me?

ASSISTANT: Sure, may I know your name please to check the status?

USER: Sure, my name is Emily Nelson.

ASSISTANT: Emily, there is no reservation found with your details.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.