I had that a few weeks ago. It wasn’t locked up but I was getting a pop up that was saying (in writing and on audio) my laptop has been found to have been hacked and something about losing data. The pop up specified don’t turn off your computer. It sounded ominous.
I texted a friend who does IT and she wasn’t positive, so I called the people at Best Buy (forgot what they’re called) and the laptop was wide open, still saying this monologue about the issue, The guy looked at it and showed me it’s not legit. He said just turn your computer off and it goes away. He showed me some site I looked at that wasn’t https and he said that’s where the problem came from. The site was some people search thing, which I went to because a former professor was giving a lecture at a local library and I wanted to see how old he was now and what else he has been doing, locally, because my daughter asked.
Something so innocent and simple caused that problem. I felt like an idiot with the guy at Best Buy, even though he was so nice about it and he said I was the third person he saw that day with the same issue. He said whatever you do, don’t call that number because they want you to download something which allows them to take control of your computer. He showed me the actual real defenses on the computer and he reassured me I was all good. I really felt foolish, like an old dinosaur who has no clue what she’s doing, even though I’m not that old lol.
The guy at Best Buy didn’t charge me for what he did, which was essentially turning off the computer and turning it back on, and talking to me about it and showing me stuff. It took about ten minutes for him, total.