I visited this place. There is a sign in the wall of this building: 
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Raikukuja 2
E F G
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So address is correct, it is 2 at the moment (maybe somebody changed it already from 1 to 2). There is also second building with the same address but different staircases but it did not have similar sign. Other buildings in this area is mapped similarly and all seem fine. So nothing to be done IMO, this is correctly mapped. So closing this one.