diff --git a/renovate.json b/renovate.json
index 546cc45..f0fc161 100644
--- a/renovate.json
+++ b/renovate.json
@@ -15,7 +15,7 @@
   "customManagers": [
     {
       "customType": "regex",
-      "fileMatch": ["^Dockerfile$"],
+      "managerFilePatterns": ["/^Dockerfile$/"],
       "matchStrings": [
         "#\\s*renovate:\\s*datasource=(?<datasource>.*?) depName=(?<depName>.*?)( versioning=(?<versioning>.*?))?\\sENV .*?_VERSION=\"(?<currentValue>.*)\"\\s"
       ],