diff --git a/instances/heimdall/configuration.nix b/instances/heimdall/configuration.nix
index a2d12b8..bc4a911 100644
--- a/instances/heimdall/configuration.nix
+++ b/instances/heimdall/configuration.nix
@@ -101,7 +101,7 @@ in
       enable = true;
       settings = {
         homeassistant = config.services.home-assistant.enable;
-        mqtt.user = "zigbee2mqtt";
+        user = "zigbee2mqtt";
         frontend = true;
         permit_join = true;
         serial = {