+ AA6YQ comments below
I noticed I have worked a CT7 station a couple times, DXKeeper assigns the DXCC identifier as LU Argentina not CT Portugal where Dave is located.
+ Two possibilities to check:
1. a logged QSO with that CT7 callsign that specifies Argentina as its DXCC entity
2. an entry for that CT7 callsign on the Override List, accessible via the "Override List" tab of DXView's Configuration window, that specifies Argentina as its DXCC entity.