diff --git a/src/ribasim_nl/ribasim_nl/model.py b/src/ribasim_nl/ribasim_nl/model.py
index 8038299..b1d45a5 100644
--- a/src/ribasim_nl/ribasim_nl/model.py
+++ b/src/ribasim_nl/ribasim_nl/model.py
@@ -296,7 +296,8 @@ def fix_unassigned_basin_area(self, method: str = "within", distance: float = 10
                             basin_df = self.basin.node.df[self.basin.node.df.distance(row.geometry) < distance]
 
                     else:
-                        ValueError(f"Supported methods are 'within' or 'closest', got '{method}'."
+                        ValueError(f"Supported methods are 'within' or 'closest', got '{method}'.")
+
                     # check if basin_nodes within area are not yet assigned an area
                     basin_df = basin_df[~basin_df.node_id.isin(self.basin.area.df.node_id)]