It changes often. Verify you are on the latest version of uBlock then force an update for any of the ad-block and Unbreak sources in your uBlock config. If that does not work de-select all of them, restart the browser and enable one at a time to see when it breaks which may require restarting the browser each time to get reliable results.

I got that about 2 weeks ago. Till new versions of the ad blockers appeared, I just used private browsing in firefox. Now I have updated all my ad blockers, seems to work OK..

Got same message in Chrome with uBlock Origin Lite when I clicked on an YouTube link.

Even worse sometimes when I'm in an Incognito window or after I've erased my browser history Google asks me to solve a captcha which made switch to DuckDuckGo for all my searches.