Sorry for the delay in reply. I've been offline.
You did it correctly. I'm starting to suspect a problem with your Windows installation. Or maybe it's because your laptop doesn't meet the minimum requirements for Windows 11.
Microsoft does not recommend installing Windows 11 on computers that are not supported. The device may malfunction due to compatibility or other issues.
As a last resort, see if disabling Driver Signature Enforcement using the other options in the article below will allow you to install the AMD driver.
https://www.itechtics.com/disable-driver-signat...
If none of the options in the article above help, then unfortunately, your best option would be to either roll back to Windows 10 or perform a clean installation of Windows 10.
This is likely due to compatibility issues between your computer and its drivers with Windows 11.
Feel free to ask back any questions. Click on the "Reply" button below my reply.
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