A coded value domain shows the value rather than the description in ArcGIS Online if the dynamic map service contains more than 25 layers referencing the same feature class.
Last Published: August 6, 2015ArcGIS Online
Bug ID Number
July 29, 2015
August 21, 2020
After review by the development team, it has been determined that this issue is related to a known limitation with the software that lies outside of Esri's control. The issue's Additional Information section may contain further explanation.
This is a known limitation for a map server. The service administrator must increase the maximum number of coded domains allowed for a service.