Mobilizon email configuration


I am trying to configure email as described in the documentation. I understood that I should append and customize the sample config to the private config:

 config :mobilizon, Mobilizon.Web.Email.Mailer,
  adapter: Bamboo.SMTPAdapter,
  server: "",
  hostname: "",
  # usually 25, 465 or 587
  port: 587,
  username: "",
  password: "aVeryStronkPassword",
  # can be `:always` or `:never`
  tls: :always,
  allowed_tls_versions: [:tlsv1, :"tlsv1.1", :"tlsv1.2"],
  retries: 1,
  # can be `true`
  no_mx_lookups: false,
  # can be `:always`. If your smtp relay requires authentication set it to `:always`.
  auth: :always

When I edit the event as admin I always get email to my admin email, but when I try to participate as guest using email my another email never receives anything being it hosted by me or gmail. My smtp works because my mastodon instance was able to send email.

Documentation mentions « Using 3rd-party mail providers will be possible in the future », I am hosting my own server on separate network than my Mobilizon will be hosted, am I therefore third party provider? Is this setup supposed to work? If this is an error are there any logs I can try to look in order to diagnose this? (I do see api requests in syslog, but nothing helpful)

I enabled registration on the server and the account confirmation emails are working, but the issue seems to be in the join as guest part. This looks like a bug so I might do a bug report, but I am not sure how reproducible it is