Try

app.py

@@ -122,12 +122,10 @@ def fetch_model_detail(submission_id):
     )
 
 def change_leaderboard_category(category):
-    return (
-        gr.DataFrame(
-            value=leaderboard_server.get_leaderboard(category=category),
-            visible=True,
-            datatype="markdown",
-        ),
+    return gr.update(
+        value=leaderboard_server.get_leaderboard(category=category),
+        visible=True,
+        datatype="markdown",
     )
 
 def show_modal():
@@ -233,8 +231,8 @@ with gr.Blocks(theme=gr.themes.Soft(text_size=text_md), css=custom_css) as main:
                 
                 category_of_tasks.change(
                     fn=change_leaderboard_category,
-                    inputs=[category_of_tasks],
-                    outputs=[results_table],
+                    inputs=category_of_tasks,
+                    outputs=results_table,
                 )
 
         with gr.Tab('Model details'):

server.py

@@ -94,7 +94,6 @@ class LeaderboardServer:
     def get_leaderboard(self, tournament_results=None, category=None):
         tournament_results = tournament_results if tournament_results else self.tournament_results
         category = category if category else self.tasks_category_overall
-        category = list(self.tasks_categories)[0]
 
         if len(tournament_results) == 0:
             return pd.DataFrame(columns=['No submissions yet'])