I'm using a 'Poll an External Website for JSON' input connector to bring in AVL data for a fleet of vehicles. I have one simple processor (field calculator to change a field data type), and then 'Write Features to Spatiotemporal Big Data Store' output connector. I'm then pulling the service that's created into Portal to display. I was hoping to view 'moving' vehicles based on the refresh interval I set in Portal, but instead, the features being written to the service from GeoEvent seem to be cumulative for each position, so I'm left with thousands of points in my Map Service instead of a few hundred. Any suggestions?