I use the ePO 4.0.0,
but since 3 months he no longer reflects a good area, for example I have a new machine in the domain but ePO can not find it, all my days are machine but ePO gives me an report that no machine is updated, the latest DAT and DAT update 6398 but in its deployment report has a DAT of March.
Thank you for your cooperation.
Without knowing what the report defines as "in compliance" and what is "out of compliance" about these clients this will be hard to answer.
Edit the report and on the "Chart" tab click the "Configure Criteria" button. This will show you what is defined as in compliance or out of compliance. Then look at the client machines being reported as out of compliance and see what specifically is out of compliance about them (do they have the wrong version of VSE? do they have an out of date DAT file? etc).