Are you using display:none and .hide() on ad unit divs?
The display property is the most important CSS property for controlling layout. This is quite often used with JS to hide or show elements on the page without deleting or recreating it.
Any element (ad) on the page can be hidden, and the page will be displayed as if the element is not there. https://www.w3schools.com/css/css_display_visibility.asp
Set up: `display: none;`
Similar to the CSS `display:none`, the `hide()` jQuery method also hides the selected elements or ads. Hidden elements will not be displayed at all. https://www.w3schools.com/jquery/eff_hide.asp
If you are hiding any ad placements on the page it will negatively affect pages viewability and send false calls to Google.
Viewability is a very important metric for advertisers so the lower viewability is the lower eCPM will be.
If this won’t be removed by the publisher Venatus will inactivate this placement to avoid policy violations with Google until issue is fixed.