Screen Time API Access

Having tried to gain access to the total daily screen time API using the text/code from the below thread, we were unable to get any data access. Has anyone else had the same issue and any resolutions? Not looking for application limits, just statistics to inform user through our 3rd party application.

Thanks for any guidance around areas we can attempt

https://developer.apple.com/documentation/deviceactivity/deviceactivitydata/activitysegment

Screen Time API Access
 
 
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