Arcade error when using FeatureSetByName to get related data

[aduyvesteyn]

I am working with a feature layer and a separate layer that intersect spatially. The layer I am trying to use in the pop-up is "Civic Addresses" and the attribute I'm trying to add in the pop-up is "FULL_ADDRESS". 

I keep getting the following error:

Execution Error: Runtime Error: Cannot call member method on null. FULL_ADDRESS

[KenBuja]

What might be happening is the editor uses the first feature in the dataset for the run. If that feature doesn't intersect the "Civic Addresses" data, the variable int will be null. You should test for that

return iif(IsEmpty(int), 'No intersecting feature', int.FULL_ADDRESS)