diff --git a/notebooks/AGIPD/Characterize_AGIPD_Gain_Darks_NBC.ipynb b/notebooks/AGIPD/Characterize_AGIPD_Gain_Darks_NBC.ipynb
index 6d2a8fda13be43c255e2c87bc0b575d7a7d60b84..deb38f6929b86f2d0533d56a0ce284a7886e568e 100644
--- a/notebooks/AGIPD/Characterize_AGIPD_Gain_Darks_NBC.ipynb
+++ b/notebooks/AGIPD/Characterize_AGIPD_Gain_Darks_NBC.ipynb
@@ -112,7 +112,7 @@
     "    show_processed_modules,\n",
     ")\n",
     "from cal_tools.tools import (\n",
-    "    CalibrationMetadta,\n",
+    "    CalibrationMetadata,\n",
     "    get_dir_creation_date,\n",
     "    get_from_db,\n",
     "    get_pdu_from_db,\n",
@@ -592,8 +592,8 @@
    "source": [
     "# Retrieve existing constants for comparison\n",
     "old_const = {}\n",
+    "old_mdata = {}\n",
     "det_mapping = {}\n",
-    "detinst = getattr(Detectors, dinstance)\n",
     "\n",
     "print('Retrieve pre-existing constants for comparison.')\n",
     "for qm in res:\n",
@@ -629,7 +629,7 @@
     "                             f'{out_folder}/old/')\n",
     "        else:\n",
     "            old_mdata[const] = \"Not found\"\n",
-    "    det_mapping[qm] = qm_db[db_module]"
+    "    det_mapping[qm] = qm_db[\"db_module\"]"
    ]
   },
   {