Unable to reinstall macOS after OCLP process

[ZNDK]

I needed to create a USB installer for Sequoia for another Mac 2020 (Intel) and I used MBP2012 (macOS Monterey/OCLP 2.1.2) to create the USB installer.
MBP then prompted me to upgrade to ver. 2.2.0 version of OCLP and I updated to 2.2.0. Then the root patch failed and could not be applied. I once tried to unroot patch and reinstall but no improvement. And I have tried to reinstall macOS from recovery mode but it won't proceed with a “can't download” dialog. When I boot with the latest version of the Monterey USB memory stick installer and try to overwrite the install, the boot disk says “downgrade not available” and cannot be selected. I gave up on Moterey and tried to install Ventura, which was also unable to install due to “cannot downgrade” I tried to install Sequoia and was able to select it. So it seems that only Sequia can be installed/upgraded normally.

- SystemVersion.plist build version mismatch: found 15.1.1 (24B91), expected 12.7.6 (21H1320)

Is there any way to reinstall Monterey other than using TimeMachine?

 

[Bigwaff]

You have to reformat your boot disk in Disk Utility after booting from USB installer. You can’t install older version macOS over newer version.

 

[PotentPeas]

Was going to say the same thing. You can't "downgrade" macOS in-place... You need to erase your disk first (obviously back up what you want to keep). If you have a Time Machine backup or other full-disk backup from before you tried upgrading, you can possibly use that to recover more easily. If not, then, something to keep in mind for future upgrade attempts...