Apple Support Scam
I had a pop-up saying my MacBook Air was locked. I did not call the number on the pop-up but called Apple support. As in most cases when you call Apple Support you wait for the next availble customer support representative. Long story short, the representative did not solve the pop-up issue. He had me run through a bunch of things. I found out later that my MacBook Air was not locked up and the pop-up issue was solved by key commands. I believe my phone call to Apple Support was intercepted. I don't feel safe calling Apple Support.
iPhone 6 Plus, iOS 12