"Unable to Update Feature
The specified foreign key field couldn't be found."
I've been running into this error when attempting to add a related feature via url from a popup in my maps. The popup is on a polygon layer which is related to a point layer - both are in the same map, both layers are editable, and my foreign key field parameter is definitely the correct field name from the point layer.
I'm a little unsure of what might be causing this and I couldn't find much documentation surrounding the addRelatedFeature field maps parameter - anyone know what might be causing this error?