diff --git a/server/nightr/app.py b/server/nightr/app.py
index 63f9720..00c41ef 100644
--- a/server/nightr/app.py
+++ b/server/nightr/app.py
@@ -38,7 +38,7 @@ def probabilities():
         try:
             prediction = strategy(context)
         except Exception as e:
-            logger.warning("Strategy '%s' failed: %s:", name)
+            logger.warning("Strategy '%s' failed:", name)
             logger.exception(e)
             continue