Some issue on SEPM Risk report:duplcate records, and what does Occurrences mean

Dear all,

I am a freshman in SEPM admin, could you kindly help me understand some issues about the SEPM risk report? Thank you in advance.

1. I can find about 5% of records in SEPM Risk report are duplicate values: 471 records in 8283. why it happened?
2. what does the volumn: occurrences mean? does it mean how many times the event happed at the specific time?
3. the actual action is cleaned by deletion, but it still kept reporting the issue, does it mean, the SEP did not find the source of the issue, and the virus file was created again and again?