diff --git a/klausur-service/backend/grid_editor_helpers.py b/klausur-service/backend/grid_editor_helpers.py
index da51ecd..e126dba 100644
--- a/klausur-service/backend/grid_editor_helpers.py
+++ b/klausur-service/backend/grid_editor_helpers.py
@@ -1333,7 +1333,7 @@ def _detect_colspan_cells(
                     })
                     logger.info(
                         "colspan detected: row %d, cols %s → merged %d cells (%r)",
-                        ri, span["cols"], len(span_cells), merged_text[:50],
+                        ri, span["cols"], len(span["cols"]), merged_text[:50],
                     )
                 break
         if not is_part_of_span: