The "Privacy and Lock" payload setting modifies Dashboard-side configurations, rather than anything local to the device. If you create a profile with only this setting and attempt to push it to a device, the profile will fail to install with an Error: "The Profile is invalid." - In general, this error usually occurs when the profile has no settings configured in the profile.
The best practice for this setting is to nest it inside a profile that has other device settings.
https://documentation.meraki.com/SM/Profiles_and_Settings/Configuration_Settings_Payloads
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
Please, if this post was useful, leave your kudos and mark it as solved.