diff --git a/bin/scripts/rfsllookups.py b/bin/scripts/rfsllookups.py
index 8833d73..7ae6267 100644
--- a/bin/scripts/rfsllookups.py
+++ b/bin/scripts/rfsllookups.py
@@ -137,6 +137,7 @@ def sumologic_populate(self):
             lookupfileid = self.lookup_ids[ioc_type]
             risklist_as_file = StringIO(self.risklists[ioc_type])
             chunks = self.split_csv(risklist_as_file, ioc_type)
+            risklist_as_file.close()
             for idx, chunk in enumerate(chunks):
                 if ARGS.verbose > 4:
                     print(f'Uploading {ioc_type} risklist chunk {idx+1} of {len(chunks)}')