diff --git a/ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py b/ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py
index 9cfb88dcd0219c5f90ddb53a19d8faa131355a0c..3966ad13b43b77372675745554f9cbdf08e05291 100644
--- a/ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py
+++ b/ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py
@@ -15,6 +15,7 @@ Some examples:
       python ./ldvspec/lofardata/scripts/migrate_ldvadmin_to_ldvspec.py --limit 1000 --host prod
 
 """
+import json
 import os
 import time
 import logging
@@ -139,10 +140,9 @@ def main():
     lst_all_dps = []
     for dps in result_query_all_dps:
         logging.debug(dps)
-        metadata_str = "{'dysco_compression': %s}" % dps[7]
         dps_dict = {"obs_id": dps[0], "oid_source": dps[1], "dataproduct_source": "LOFAR LTA",
                     "dataproduct_type": dps[2], "project": dps[3], "activity": dps[4], "surl": dps[5],
-                    "filesize": dps[6], "additional_meta": metadata_str, "location": dps[5]}
+                    "filesize": dps[6], "additional_meta": {"dysco_compression": dps[7]}, "location": dps[5]}
         lst_all_dps.append(dps_dict)
 
     if no_limit_to_insert:
@@ -150,12 +150,10 @@ def main():
         logging.info("Added {} DataProduct objects".format(len(res_lst_ids)))
         logging.debug("Added with ids={}".format(res_lst_ids))
     else:
-        cnt = 0
         nbr_required_inserts = math.ceil(len(lst_all_dps)/args.max_nbr_dps_to_insert_per_request)
         for cnt in range(nbr_required_inserts):
             start = cnt * args.max_nbr_dps_to_insert_per_request
             end = start + args.max_nbr_dps_to_insert_per_request
-            cnt += 1
             res_lst_ids = ldvspec_interface.insert_multiple_dataproduct(payload=lst_all_dps[start:end])
             logging.info("Insert count {} of {}: Added {} DataProduct objects  [{} till {}]".
                          format(cnt, nbr_required_inserts, args.max_nbr_dps_to_insert_per_request, start, end))