Enter AppleID password pop up keeps popping
I have a choice of Later and Preferences. I choose later it pops up a second later. If I choose Preferences and enter the correct password and sign in, a couple seconds later the original pop up shows again. Just keeps repeating itself.
I have signed out of all devices, changed the pw and same result. I can still use my pc but I cannot move the pop up and it’s right in the middle of my screen. What can I do to stop this?
MacBook Pro 13″, OS X 10.11