Hello - I was having issues with my Field Maps pop-ups throwing errors b/c I was accessing a map configured using Map Viewer. I saved a copy of the map, re-configured pop-ups in Map Viewer Classic, and have eliminated the error message.
However, now I have my two pop-up fields - which both point to related-table fields - showing up as blank in the Field Maps pop-up. When I click on the related-table attributes in field maps, those two fields show up as populated, but the pop-up still shows them as blank. In the ArcGIS Online map (using Map Viewer Classic), the pop-up shows up correctly, with the populated related-table field values.
My AGOL map is accessing data from an Enterprise feature service.
I'm using Field Maps on iOS, app version 22.4.2, Build 954.