1) I can find about 5% of records in SEPM Risk report are duplicate values: 471 records in 8283. why it happened?
SEP client duplicate entry are available in SEPM console.
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?
Look this discussion
https://www-secure.symantec.com/connect/forums/clean-and-clean-deletion