diff --git a/src/charm.py b/src/charm.py
index 92ccbeaa..26d068ef 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -725,7 +725,7 @@ def _is_bessd_configured(self) -> bool:
             logger.debug("bessd configured workers: %s", stdout)
             return True
         except ExecError as e:
-            logger.info(f"Configuration check: {e}")
+            logger.info("Configuration check: %s", e)
             return False
 
     def _configure_bessd_for_dpdk(self) -> None: