Clear-AssignedAccess cmdlet clears the AssignedAccess configured account settings and returns the user to default settings. It’s a simple cmdlet, open PowerShell and run the cmdlet as shown below.
Use PowerShell to clear Assigned Access
PS C:> Clear-AssignedAccess
This can also be removed by using the local settings https://techdirectarchive.comm/2020/01/18/disable-or-remove-kiosk-mode-via-the-local-settings/
To see how this is done for MDM AssignedAccess, see https://techdirectarchive.com/2020/02/13/how-to-delete-an-instance-assignedaccess-when-applied-via-mdm-wmi-bridge-provider/