For further reference:
U.S. Federal Trade Commission – How To Spot, Avoid, and Report Tech Support Scams
Tech support scammers may try to trick you with a pop-up window that appears on your computer screen. It might look like an error message from your operating system or antivirus software, and it might use logos from trusted companies or websites. The message in the window warns you about a security issue on your computer and tells you to call a phone number to get help.
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If you get this kind of pop-up window on your computer, don’t call the number. Real security warnings and messages will never ask you to call a phone number."
U.S. Federal Bureau of Investigation – Tech Support Scams
Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Apple Support
"… scammers use any means they can to trick you into sharing information or giving them money, including … fraudulent emails and other messages that look like they're from legitimate companies, including Apple [and] misleading pop-ups and ads that say your device has a security problem."
"While browsing the web, if you see a pop-up or alert that offers you a free prize or warns you about security problems or viruses on your device, don't believe it. These types of pop-ups are usually fraudulent advertisements, designed to trick you into downloading damaging software or giving the scammer personal information or money."