I have a dashboard containing a number of layers. Most of them are responding fine to actions configured in category selectors in the sidebar. There is one layer however, which has stopped responding. Selecting the category now has no effect on the layer when previously it would apply a filter.
The layer still visually displays without issue, and also correctly feeds into an Indicator (which updates with spatial selection). I have tried creating a new copy of the layer, which I uploaded to AGOL, however this layer suffers from the same behaviour when referenced in the same dashboard. Both this 'new' layer, and the old one, have a blue flashing dot next to them in the Layers controller suggesting they are still loading, however this flashes continually even when all features are displaying. Is this 'hanging' behaviour responsible for the issue? How can I fix it?
When I create a fresh dashboard, the layers respond and filter correctly - however using 'Save As' to create a new instance of the existing dashboard does not fix the issue.

Filter not acting on the map (left) and blue loading dots (right)