Email-based 2FA attempted on Vaultwarden instance, but no Email is ever received

[LordMZTE]

The issue

When I attempt to log into my Vaultwarden instance, I get:

Log in to mzte.de
Master Password: 
Enter the PIN you received via email.
Email Code:

But there is never eny email sent. Logging into the web UI via Email 2FA works just fine.

System information

• OS: NixOS
• rbw -V: rbw 1.15.0
• Vaultwarden version: 1.35.2
• rbw config show:

  {
    "email": "lord@mzte.de",
    "sso_id": null,
    "base_url": "https://mzte.de/vault",
    "identity_url": null,
    "ui_url": null,
    "notifications_url": null,
    "lock_timeout": 3600,
    "sync_interval": 3600,
    "pinentry": "pinentry",
    "client_cert_path": null
  }

If you would like an account on my instance for testing, I can send you an invite Email.