diff --git a/regexmodel/regexclass.py b/regexmodel/regexclass.py
index e326dc9..62134f0 100644
--- a/regexmodel/regexclass.py
+++ b/regexmodel/regexclass.py
@@ -260,6 +260,7 @@ def get_candidates(cls, series: pl.Series,
         else:
             score_sub = 0
             regex = cls()
+            next_series_sub = next_series_full
 
         if score_full >= score_sub:
             if score_full > 0:
@@ -324,7 +325,7 @@ def score(series: pl.Series, regex: BaseRegex, count_thres: int,
     fraction_match = next_not_null/cur_not_null
     fraction_cover = n_unique/regex.n_possible
 
-    expected_finish = fraction_match**avg_len_next*next_not_null
+    expected_finish = fraction_match**avg_len_next*next_not_null  # type: ignore
     expected_finish = max(1e-12, expected_finish)
     split_penalty = 1/(1 + count_thres/expected_finish)
     cur_score = regex.subrange_penalty*split_penalty*fraction_cover*fraction_match