Can’t receive email preview to my ghost admin address and users can’t signup

I can’t receive post newsletter preview to my ghost admin email, but I get it if I send it to a different mail.

Additionally, users can’t signup.

I set config json to send mail with mailgun, ghost latest edition at

I changed support and newsletter email to my ghost admin email.

Can anyone help understand what I need to fix?

Are you using a Mailgun sandbox domain or have you not finished setup for your custom domain in Mailgun? Until setup is complete Mailgun will only allow certain email addresses to be emailed.

@Kevin I have a custom domain in Mailgun, and I set the config.production.json with its login user mail and password (after reset). Also added Mailgun private key in the newsletter settings.

Have you checked your Mailgun events/logs for deliverability?

Mail to ghost admin email are accepted but not delivered. I totally ignore what lo look for.
mail delivered in dashboard are 100%