diff --git a/invenio_config_tuw/formatters.py b/invenio_config_tuw/formatters.py
index b8dff170fc5021748e1e6d3ac0de7516037a8275..0b36d0c682e728f672a6a9e23c3547a1cf0ed239 100644
--- a/invenio_config_tuw/formatters.py
+++ b/invenio_config_tuw/formatters.py
@@ -35,8 +35,10 @@ class CustomFormatter(Formatter):
         super(CustomFormatter, self).__init__(fmt=fmt, **kwargs)
 
     def format(self, record):
-        record.user_id = (
-            current_user.id if current_user.is_authenticated else "Anonymous"
-        )
+        user_id = "Anonymous"
+        if current_user is not None and current_user.is_authenticated:
+            user_id = current_user.id
+
+        record.user_id = user_id
         record.request_url = request.base_url
         return super(CustomFormatter, self).format(record)