If your system appears to be failing, drop down to a lower-level tool.
We don’t always know why a drive connected to a Mac starts to fail or the system becomes sluggish and nothing helps. If you’ve gone through routine troubleshooting and nothing fixes the problem—including reinstalling macOS as a last resort—you may want to try to recover the startup volume’s contents by booting using recoveryOS, a special partition in macOS designed for helping with what it says on the label: recovery!
First, restart your Mac into recoveryOS:
- With an Intel Mac, choose > Restart or power up your Mac. Hold down Command-R during startup until you see the progress bar beneath the Apple icon.
- With an M1 Mac, power down your Mac normally if it’s active (via > Shut Down). Then hold down the power button until “Loading startup options” appears, which can take about 10 seconds. Eventually, one or more drive icons will appear along with the Options icon. Click the Options icon and log in with an administrator account if prompted.
Read more at MacWorld.com