bug fix for empty `my submission`

competitions/submissions.py

@@ -138,7 +138,7 @@ class Submissions:
         submissions_df = pd.DataFrame(team_submissions_info["submissions"])
 
         if len(submissions_df) == 0:
-            return pd.DataFrame(), pd.DataFrame()
+            return pd.DataFrame()
 
         if not private:
             submissions_df = submissions_df.drop(columns=["private_score"])