diff --git a/spotify.ipynb b/spotify.ipynb
index 5a68a53..0f7bf8e 100644
--- a/spotify.ipynb
+++ b/spotify.ipynb
@@ -54,7 +54,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 186,
+   "execution_count": 189,
    "id": "a898326e",
    "metadata": {},
    "outputs": [],
@@ -71,6 +71,9 @@
     "    return df.withColumnRenamed(\"master_metadata_album_album_name\", \"album_name\").withColumnRenamed(\"master_metadata_album_artist_name\", \"artist_name\").withColumnRenamed(\"master_metadata_track_name\", \"track_name\")\n",
     "\n",
     "def rename_columns(df, rename_map):\n",
+    "    missing = set(rename_map) - set(df.columns)\n",
+    "    if missing:\n",
+    "        print(f\"Warning: columns not found: {missing}\")\n",
     "    return df.toDF(*[rename_map.get(c, c) for c in df.columns])\n",
     "\n",
     "def track_df(df):\n",
@@ -82,7 +85,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 191,
    "id": "c609291c",
    "metadata": {},
    "outputs": [],