Each time a layer is updated in your Field Tool app (by toggling it on or by an auto-cache refresh due to time or distance traveled), the updated data only includes the closest data based upon the radius settings.  This means that, if you travel away from an area, data may not be loaded and it looks like it has disappeared.  It truly is saved, though, and will be updated to Intterra when you return to an area with good comms.

For additional information, see: