Your layer relies on a custom feature and you are sharing as a web layer to ArcGIS Online hosted services. For the layer to perform as expected, the custom feature must also be registered on the server. Custom features are not supported by ArcGIS Online web layers.
Remove the layer from your map.
Custom features allow you to customize geodatabase behavior. For layers utilizing custom features to work as expected within a web layer, the custom feature must be available to the server. If the custom feature is not accessible by the server, the specialized behavior, or functionality, will be unavailable on the web layer.