diff --git a/sage_validation/file_validator/forms.py b/sage_validation/file_validator/forms.py
index a5a7b749ff24c774928408ce8a63b66154c7c4a7..e3a2929a068a5d8337a695fb41f706a6f7a81619 100644
--- a/sage_validation/file_validator/forms.py
+++ b/sage_validation/file_validator/forms.py
@@ -63,7 +63,7 @@ class CSVUploadForm(forms.Form):
                         )
 
             if missing_columns:
-                err_msg = f"Missing required columns: {", ".join(missing_columns)}"
+                err_msg = f"Missing required columns: {', '.join(missing_columns)}"
                 raise forms.ValidationError(err_msg)
 
         except (UnicodeDecodeError, csv.Error) as e: