OSM - Mapnik - areas rendered as background color - openstreetmap

I am generating maps using Mapnik and OSM data (postgres and shapefiles). My problem is that quite a few areas, most of which I believe are considered "landcover", are rendering as the background color. The areas render as background color regardless of zoom level.
For example, in between streets, everything is blue. There are some forests that render as expected, but most of the residential areas are just blue.
I am using Mapnik 3 with a stylesheet. This is running on Ubuntu 16.04.
The images below show what I am generating, and what I would like to see (based on what is on Openstreetmaps).
Any suggestions as to where I should look to solve this problem would be greatly appreciated.
Thanks.
What I'm getting
OSM

The problem was caused by some invalid zoom levels and/or MinScaleDenominator, MaxScaleDenominator values. I have not narrowed it down completely, but by removing those attributes, I'm seeing the land again.
Thank you for the help.

It is an issue with your stylesheet, if it's a custom one I recommend loading it into TileMill and playing around the LandCover and Area colours until you're satisfied.
If you were wanting a relevant point of reference, check out the Stylesheet Configuration to get your own copy of OSMBright, so you can compare the rendering styles.
Update A link for the OSM style look: https://github.com/gravitystorm/openstreetmap-carto

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Here is a screenshot for clarification
The data comes from a postgis database, I just export it to a CSV and upload it to mapbox.
I have tried converting the Multipolygon into single Polygons but that ended in the same result.
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In Mapbox Studio Classic (desktop application), Map refers to all of the land, and (if you're using mapbox-streets-v5 or mapbox-streets-v6 as your data source) #water has its own selector. If you set Map to some color value, all of the land will be that color. If you set #water to some color value, all of the water will be that color. Keep in mind also that rivers and streams can be styled via the #waterway selector.

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I am following the source quickstart tutorial. I have followed the tutorial all the way through, and am having trouble displaying the earthquake data (red circles) above the land vectors.
According to the symbol drawing order documentation:
“Higher” layers obscure “lower” ones.
However I'm not finding this to be the case. Please see attached screenshot:
The 'earthquakes' layer is the 'higher' layer, I think. I am using the 'Comic!' base map styles. Since the road lines also appear to 'mask off' the land vectors and show the earthquake data below, I'm wondering if this is causing the issue, but looking through the styles there's nothing obvious I can see.
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http://wiki.openstreetmap.org/wiki/Featured_tiles

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