This happens because this search list, like all search lists, excludes inactive constituents by default and there isn't a way to change this setting on an import to include inactive constituents.
As a workaround, if the interaction needs to be imported, users can mark the constituent active to successfully import the interaction, then change the constituent back to inactive. Otherwise, an interaction can be added to an inactive constituent either by manually adding a row in batch or on the inactive constituent record.
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