Unable to turn on screen time restrictions

There could be something in the main User Account playing up.

Suggest downloading the Application Etrecheck directly from a well Respected ASC Contributor. And Safe to use.

The application is free or paid from added features. 

Run the application with Full Disc Access ( Security & Privacy - Full Disc Access ).

It will take a Snap Shot -  both the hardware and software.

 The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - using the Additional Text Icon ( 3rd Icon to last )

We can have a look at the report for possible issues and may have possible suggestions to resolve the issues.

Any Third Party Applications that will interfere with the normal operation of the OS, alter, modify, remove or delete or attempt to do so is an invitation for disaster and may require a Reinstallation of the OS in-order to replace any modified, altered, removed or corrupted elements of the OS this software has inflected on this computer 

Although some or all of these Applications maybe available on the Apple Apps Store, it does not mean Apple has verified what exactly the Application can do, does do or is doing to the Computer. That responsibility is left to the User to perform their due diligence on the Application before purchasing and installing it.

Any of the below should be removed as per Developers Instructions 

This includes AntiVirus, Disk Cleaners, Disk Optimizes, UnInstaller etc.

This will include CleanMyMac , This will include BitDefender , 

This will included Norton Antivirus , Sophos Av Software

Intego AntiVirus, McAfee, MacKeeper, Avast AntiVirus

Ad Guard, Webroot

The The Built in Security  is all that is required.

Hi mcsummitt,

Are you trying to turn on Screen Time for your personal device, or on a child's device using parental controls and Family Sharing? If the option is greyed out, it's possible there is a restriction enabled that is preventing you from making account changes. When you get a chance, check out Use parental controls on your child's iPhone, iPad, and iPod touch and see if it helps.

Best regards.

mcsummitt,

Thank you for clarifying. Let's verify you have the correct date and time set on your Mac.

This article should help: Set the date and time on your Mac

Next, let's test in safe mode: How to use safe mode on your Mac

Let us know if anything changes.

Good Luck!