The ArcGIS Experience Builder Query widget provides multiple values when creating a clause for a service that contains multiple symbology attributes.

Solución alternativa

1. Open the feature service in Map Viewer.
2. Select the service in the Layers pane, and select styles on the Settings (light) toolbar.
   1. Only one field will be included in the 'Choose attributes' section.
3. Add another field and select the second field you added to the symbology in ArcGIS Pro.
4. Save as a new web map.
5. Repeat the steps in ArcGIS Experience Builder, and the clause will only include the values for the first field as expected.

Pasos para reproducir