Hi there,
As you have already joined the Insider the only option would be to update to Win 11 or clean install the PC to win 10 stable versions.
If the update was done in the last 10 days try to move to your old stable version in the recover section in the settings.
Open Settings and make sure the 'System' tab is selected.
Scroll down and select the 'Recovery' option.
Under 'Recovery options', you should see a 'Previous version of Windows' section. ...
From the window that appears, choose any of the options and click 'Next'
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