This happens if the underlying dataset changes names, e.g. from "time" to "modified_time", and there is just a single time in the table.
The UI will show the new name, and since there is a single value, won't allow modifications. But the UI code reacts only to change events, instead of using a MapModel that would feed into the metadata map the right values on submit, as a result, the UI gives the illusion of the config being changed, but in fact, it's not.