I have a single feature in a cartodb which I am pulling into my HTML page using
var layerUrl = 'path-to-/viz.json';
And I can see the layer on some zoom scales but others it vanishes.
It can't be a conflict with another geometry as there are no others in the table.
The path to a test viz is here: https://osnhs.cartodb.com/api/v2/viz/39628358-3206-11e5-8ec0-0e4fddd5de28/viz.json
My HTML page enables a user to draw a polygon using the Leaflet draw polygon tool and this is then saved to a table.
This table is then used for the viz.json
It seems the polygon does not show at the zoom level that the polygon is drawn at. If I zoom one level out or in the polygon appears.
Unfortunately, I cannot share the complete HTML but I used the following example http://bl.ocks.org/matallo/130b969a6cc76939985d