Cant update from windows 10 to 11

• PCHealthCheck confirms I'm OK to upgrade.
• Unplug all the USB devices.
• sfc /scannow -> no issues
• chkdsk c: /scan -> no issues
• I have tried doing the update 3 ways: (1) “check for updates” (2) Windows 11 Installation Assistant, (3) ISO. Each has failed – sometimes with different errors. The “check for updates” method has apparently given up and doesn’t even offer an upgrade to Windows 11 anymore. So this time I try with the ISO, but I've seen the same result described below using the "check for updates" method.
• I start the update and everything proceeds nicely until the stage in the install where it is “Working on updates” and “may need to restart a few times”. After a restart, a screen flashes by too quick to see and a message pops up that it is undoing the changes. Eventually, the Windows 11 Setup informs me of the following error:

We couldn’t install Windows 11 ...

0x8007000D - 0x2000C

The installation failed in the SAFE_OS phase with an error during APPLY_IMAGE operation.

I have no knowledge of pc's please help.