diff --git a/charts/mail-gateway/templates/mx-certificate.yaml b/charts/mail-gateway/templates/mx-certificate.yaml
index c4012ae..2999b08 100644
--- a/charts/mail-gateway/templates/mx-certificate.yaml
+++ b/charts/mail-gateway/templates/mx-certificate.yaml
@@ -4,7 +4,7 @@
   name: {{ .Values.domains.primary.mx }}
   namespace: {{ .Release.Namespace }}
   annotations:
-    "helm.sh/resource-policy": keep
+    helm.sh/resource-policy: keep
 spec:
   dnsNames:
   - {{ .Values.domains.primary.mx }}