how to fix notification not show button? When i receive file via bluetooth, notification is show but don't have any button for accept or cancel.
These are just notifications, letting you know that something happened, not dialogues expecting your actions.
Yes, you cannot do anything with or about it from that notification. If you want to do anything regarding the notification, you must go to the option it is referring to, in your case, it is the bluetooth option. This might seem weird for an ex-windows user that is used to getting an action upon clicking the notification but this is how eOS works.