Performance Monitor Counter disappearing


I’m currently montioring the GPU Memory Usage.
Therfore I request via WMI the Counter you can add through Windows perfmon.

But somehow the counter will get “empty” at any time.
My WMI query throws an error.
When I open perfmon to verify the counters the Instances for the selected object don’t appear.

the first time I saw this, I resetted the WMI counters.
They worked a while again.
Today the issue came up again, and meanwhile I was troubleshooting this, the counters worked again.
So the counter are reachable sometimes and sometimes not.
This can be also seen on my graph which has missing data for some periods.

Anyone there with an explanation for this?