diff --git a/mlair/plotting/postprocessing_plotting.py b/mlair/plotting/postprocessing_plotting.py
index 00c925031e8e8bc804979c75052355837f5cb614..a3f69ba6910ee5c1046a1393f3e21513b1a68253 100644
--- a/mlair/plotting/postprocessing_plotting.py
+++ b/mlair/plotting/postprocessing_plotting.py
@@ -748,7 +748,7 @@ class PlotCompetitiveSkillScore(AbstractPlotClass):
         fig, ax = plt.subplots(figsize=(size, size * 0.8))
         data = self._filter_comparisons(self._data) if single_model_comparison is True else self._data
         if self._model_name_for_plots is not None:
-            data['comparison'] = [i.replace('nn-', f'{self._model_name_for_plots}-') for i in data['comparison']]
+            data.loc[:, 'comparison'] = [i.replace('nn-', f'{self._model_name_for_plots}-') for i in data['comparison']]
         order = self._create_pseudo_order(data)
         sns.boxplot(x="comparison", y="data", hue="ahead", data=data, whis=1., ax=ax, palette="Blues_d",
                     showmeans=True, meanprops={"markersize": 3, "markeredgecolor": "k"}, flierprops={"marker": "."},
@@ -766,7 +766,7 @@ class PlotCompetitiveSkillScore(AbstractPlotClass):
         fig, ax = plt.subplots()
         data = self._filter_comparisons(self._data) if single_model_comparison is True else self._data
         if self._model_name_for_plots is not None:
-            data['comparison'] = [i.replace('nn-', f'{self._model_name_for_plots}-') for i in data['comparison']]
+            data.loc[:, 'comparison'] = [i.replace('nn-', f'{self._model_name_for_plots}-') for i in data['comparison']]
         order = self._create_pseudo_order(data)
         sns.boxplot(y="comparison", x="data", hue="ahead", data=data, whis=1., ax=ax, palette="Blues_d",
                     showmeans=True, meanprops={"markersize": 3, "markeredgecolor": "k"}, flierprops={"marker": "."},