I suspect calling Apple Support is a hack. Is it?
System iMac 27" mid 2012 OS 10.13 High Sierra
While using Google to research, it produced a local, small on line and print news bureau with info I was searching. It is legitimate, I've done business with them. I clicked its "Download" button that produced messages that my computer was taken over locked [it was] and directed me to call 1-844-621-**** which I did NOT.
I had to do a power off and startup to get out of lock up condition.
I've contacted the news bureau whose tech is going to return my call.
[Edited by Moderator]
iMac 27″, macOS 10.13