the features will not display on the map in GIS Online but they are visible in Collector and Explorer.
Has happened before with other layers.
Has anyone experienced this and how did you resolve it.
Are you able to share the layer or web map? If not, I'd suggest getting in touch with technical support.
Also, check the visible scale range of the layer. Features on Collector are usually viewed at a large scale (zoomed in), so sometimes, zooming out in the web map may make the layers disappear if the visible scale range has been selected. This is a bit of a guess based on your description, so please get in touch with us if the issue is still happening.
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