Why am I receiving device scanning alerts on my iPhone?

An alert saying "scanning your device" might be from a security app or built-in feature. Check which app or setting triggered it. If it seems suspicious or you don’t recognize the source, restart your phone and run a security scan. If the issue persists, consider contacting Apple Support.

FTC – 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."

Scam messages of some sort?