fix a bug

app.py

@@ -197,6 +197,7 @@ with gr.Blocks() as demo:
         fn=generator.generate_mesh,
         inputs=[block_prompt, cache_image_base64, cache_task_uuid],
         outputs=[cache_raw_image, cache_task_uuid, fake3d],
+        queue=True
     ).success(
         fn=do_nothing, 
         js=change_button_name, 
@@ -229,6 +230,7 @@ with gr.Blocks() as demo:
         fn=generator.generate_mesh,
         inputs=[block_prompt, cache_image_base64, cache_task_uuid],
         outputs=[cache_raw_image, cache_task_uuid, fake3d],
+        queue=True
     ).then(
         fn=do_nothing, 
         js=change_button_name, 
@@ -261,4 +263,5 @@ with gr.Blocks() as demo:
 
 
 if __name__ == "__main__":
+    demo.queue()
     demo.launch(show_api=False, show_error=True)