Update nbfi.py

nbfi.py

@@ -230,6 +230,7 @@ class NBFI(datasets.GeneratorBasedBuilder):
         data = data[~data.Client_Family_Members.isna()]
         data = data[~data.Social_Circle_Default.isna()]
         data = data[~data.Population_Region_Relative.isin(("@", "#"))]
+        data = data[~data.Population_Region_Relative.isna()]
         data = data[data.Loan_Annuity != "#VALUE!"]
         data = data[data.Age_Days != "x"]
         data = data[data.Employed_Days != "x"]