diff --git a/config/packages/monolog.yaml b/config/packages/monolog.yaml
index 8938cc13d..44a078b85 100644
--- a/config/packages/monolog.yaml
+++ b/config/packages/monolog.yaml
@@ -50,7 +50,6 @@ when@prod:
                 type: stream
                 path: "%kernel.logs_dir%/%kernel.environment%.log"
                 level: debug
-                formatter: monolog.formatter.json
             console:
                 type: console
                 process_psr_3_messages: false
@@ -74,7 +73,6 @@ when@docker:
                 type: stream
                 path: "php://stderr"
                 level: debug
-                formatter: monolog.formatter.json
             console:
                 type: console
                 process_psr_3_messages: false