When the First Aid process is complete, click Done. In the First Aid dialog, click Run, then follow the onscreen instructions. In the sidebar, select a volume, then click the First Aid button. If you check your startup volume (Macintosh HD), make sure you also check your data volume (Macintosh HD - Data).
Note: If you’re checking your startup disk or startup volume, restart your computer in macOS Recovery, select Disk Utility in the macOS Recovery window, then click Continue.
