Hi @ahargreaves_FW ,
Geocoding addresses and storing the value into a field uses credits, which means an account needs to be tied to the ArcGIS World Geocoding Service.
In ArcGIS Portal, you can store the credentials for an ArcGIS Online account to be used for consuming credits. In your organization settings, configure the Geocode utility and provide the credentials to use. Here's some related doc: Utility services—Portal for ArcGIS | Documentation for ArcGIS Enterprise
This will create a new Locator item in your Portal Content.
Make sure to use the service URL from that item as the Geocoder URL in the Smart Editor settings.
( from your screenshot above, insert the URL here: )
Once this is set, the users should not be prompted to sign in anymore, and credits will be consumed from that ArcGIS Online account directly.