diff --git a/sso-mfa/k8s/authelia/configmap.yaml b/sso-mfa/k8s/authelia/configmap.yaml
index 4aa845b..ca1a675 100644
--- a/sso-mfa/k8s/authelia/configmap.yaml
+++ b/sso-mfa/k8s/authelia/configmap.yaml
@@ -114,6 +114,7 @@ data:
               - groups
             grant_types:
               - authorization_code
+            token_endpoint_auth_method: client_secret_post
             response_types:
               - code
             response_modes: