Cannot send email from custom domain
I have followed this guide https://support-en.mailbox.org/knowledge-base/article/e-mail-addresses-of-your-own-domain
Successfully setup Security Key, Add alias, MX records, SPF records, and even setup auto config.
However when logging in with my custom domain as primary I get this error.
There was an issue while authenticating. This may be due to a recent password change. To continue please log out and log back in with your most current password.
I cannot send email with my custom domain, but can receive mail which goes to my @mailbox.org account.