Google has confirmed they are experiencing a technical display issue affecting review counts on some Google Business Profiles. This is purely a display problem - no actual reviews have been deleted or lost. Google's team is actively working to fix this and restore the correct review counts.
There is no action needed from your end. Simply wait for Google's technical team to implement their fix, which they are prioritizing. They will provide updates in the Google Business Profiles Forum as the situation progresses.

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