Hi,
In general, mouse pointer shows the spinning circle state means some programs are loading or system is busy, but you said that system is idle, it’s very strange.

Please check if you have customized pointer scheme or used some programs that can change pointer’s style.
If not, I think there is something running in background, when your mouse pointer becomes spinning circle, open task manager to see which process is consuming more resources, kill it to see the result.
In addition, close your security software and remove all scan schedule.
Regards
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