The map has more than one parcel layer that connects to the same parcel fabric feature class. For example, one parcel layer displays current parcels and second parcel layer connecting to the same feature class displays historic parcels.
Solutions
For publishing purposes, remove the duplicate layer that connects to the parcel fabric feature class. After publishing, multiple layers referencing the same parcel fabric feature class can be configured when the parcel fabric is added to the map from a portal.
Additional information
For more information, see Add the parcel fabric to the map and Analyze your GIS resource.