Cannot login with MFA enabled

[agross]

Hello,

Thank you for creating AutoKuma. I'm currently trying to get it set up, but I'm not able to log in with MFA enabled. I'm using the builtin auth of Uptime Kuma (i.e. single user). I verified that I'm able to log in with the credentials on the web, but AutoKuma (2.0.0 and 2.1.0-rc.2) logs:

app-1       | 2026-06-26T19:44:50+02:00 [SOCKET] INFO: New websocket connection, IP = 172.28.0.3
app-1       | 2026-06-26T19:44:50+02:00 [AUTH] INFO: WebSocket with no origin is allowed
app-1       | 2026-06-26T19:44:50+02:00 [AUTH] INFO: Login by username + password. IP=172.28.0.3
app-1       | 2026-06-26T19:44:50+02:00 [RATE-LIMIT] INFO: remaining requests: 19
app-1       | 2026-06-26T19:44:50+02:00 [AUTH] WARN: Invalid token provided for user the-user. IP=172.28.0.3
autokuma-1  | 2026-06-26 17:44:50.340 [kuma_client::client] WARN: The server rejected the login: authInvalidToken
autokuma-1  | 2026-06-26 17:44:50.340 [kuma_client::client] WARN: Error while handling 'Info' event: The server rejected the login: authInvalidToken
autokuma-1  | 2026-06-26 17:44:59.141 [kuma_client::client] WARN: Timeout while waiting for Kuma to get ready...
autokuma-1  | 2026-06-26 17:44:59.143 [autokuma::sync] WARN: Encountered error during sync: It looks like the server is expecting a username/password, but none was provided

I tried logging the HTTP traffic between app and autokuma and I found:

["loginRequired"]
[{"ok":false,"msg":"authInvalidToken","msgi18n":true}]

services:
  app:
    image: louislam/uptime-kuma:2.4.0
    volumes:
      - app:/app/data
      - /var/run/docker.sock:/var/run/docker.sock
    # Elided Traefik labels.
    environment:
      TZ: Europe/Berlin
      UPTIME_KUMA_DB_TYPE: sqlite

  autokuma:
    image: ghcr.io/bigboot/autokuma:2.1.0-rc.2
    environment:
      AUTOKUMA__KUMA__URL: http://app:3001
      AUTOKUMA__KUMA__USERNAME: the-user
      AUTOKUMA__KUMA__PASSWORD: the-password
	   # Copied from my password manager and verified with https://totp.danhersam.com/
      AUTOKUMA__KUMA__MFA_SECRET: MFEHEVZSONRUK4DIMJ4VAVZQGM3WQZ2NGA3EW4KOG54GWTKXJQ4TQV2XGRZFGOLOMU3VKQRVJA3WIUSXI5LFG32DPJEWK5TLMFMXGSA

      AUTOKUMA__ON_DELETE: keep

      AUTOKUMA__DOCKER__ENABLED: false
      AUTOKUMA__FILES__ENABLED: true
      AUTOKUMA__STATIC_MONITORS: /static
    volumes:
      - autokuma-data:/data
      - ./static:/static:ro