diff --git a/nannyml/runner.py b/nannyml/runner.py
index 38e395de..dcba9cc8 100644
--- a/nannyml/runner.py
+++ b/nannyml/runner.py
@@ -298,6 +298,6 @@ def _add_targets_to_analysis_data(
     analysis_data: pd.DataFrame, target_data: pd.DataFrame, join_column: Optional[str]
 ) -> pd.DataFrame:
     if join_column is not None:
-        return analysis_data.merge(target_data, on=target_data.join_column)
+        return analysis_data.merge(target_data, on=join_column)
     else:
         return analysis_data.join(target_data)
diff --git a/setup.cfg b/setup.cfg
index af714661..1f1c9658 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,7 +1,7 @@
 [flake8]
 max-line-length = 120
 max-complexity = 18
-ignore = E203, E266, W503
+ignore = E203, E266, E704, W503
 docstring-convention = google
 per-file-ignores = __init__.py:F401
 exclude = .git,
@@ -62,7 +62,7 @@ python =
 [testenv]
 allowlist_externals = pytest
 deps =
-    pytest
+    pytest==6.2.5
     pytest-cov
     pytest-mock
     pytest-lazy-fixture