You’re missing database migrations. You can hardly expect Zammad to go on without issues.
Ensure that within the admin settings > Objects the didn’t forget the “Update database” button. Hit it if it’s there. Restart Zammad after. As safety measure, also run zammad run rake db:migrate
After that run zammad run rails r 'Channel::EmailParser.process_unprocessable_mails' to import the mails Zammad couldn’t import