Adding an extra value to a coded value domain of a hosted feature layer published from ArcGIS Pro and has domains and subtypes defined returns the "Domain already exists" error message in the ArcGIS Field Maps app.

Workaround

• Remove the value of the domain that is added after publishing the layer.
• Add the extra value to the domain in ArcGIS Pro and re-publish the layer from ArcGIS Pro.

1. Navigate to the REST API in ArcGIS Online and find the layer to update.
2. Change /rest/services/ in the URL to /rest/admin/services/ and press Enter.
3. Navigate to Update Definition.
4. Make the appropriate changes to the JSON code by updating the domains listed under the subtypes.
5. Click Update Layer Definition.

Steps to Reproduce