fix bug in recolor_umap

app.py

@@ -228,7 +228,7 @@ def recolor_umap(obs_col, coords, h5ad_path):
             return str(out_png.resolve())
         if n_cat <= 1:
             gr.Info(f"'{obs_col}' has a single category. Showing uncolored UMAP.")
-            out_png = draw_uncolored(f"{obs_col}: 1 category")
+            out_png = draw_uncolored(coords, f"{obs_col}: 1 category")
             return str(out_png.resolve())
 
         # draw with legend