diff --git a/app/terraform/block_external.py b/app/terraform/block_external.py
index 56de93d..4b19b64 100644
--- a/app/terraform/block_external.py
+++ b/app/terraform/block_external.py
@@ -36,7 +36,7 @@ class BlockExternalAutomation(BlockMirrorAutomation):
     def fetch(self) -> None:
         user_agent = {'User-agent': 'BypassCensorship/1.0'}
         if isinstance(app.config.get('EXTERNAL_CHECK_URL', []), list):
-            check_urls = app.config['EXTERNAL_CHECK_URL']
+            check_urls = app.config.get('EXTERNAL_CHECK_URL', [])
         elif isinstance(app.config.get('EXTERNAL_CHECK_URL'), str):
             check_urls = [app.config['EXTERNAL_CHECK_URL']]
         else: