Redmine

I found out we seem to have a problem with incoming emails not being updated into redmine. Our setup goes via Google Apps, and the messages get forwarded to our postfix-server:

user sends message to support@ourdomain.tld that is handled by googlel apps. The message get's routed back to our redmine-server that responds on support-add@redmineserver.ourdomain.tld

In postfix i have configured an alias that runs the rdm-mailhandler.rb

/usr/local/rvm/rubies/ruby-2.3.0/bin/ruby /etc/postfix/rdm-mailhandler.rb \
--project support   \
--tracker New issues \
--unknown-user create \
--no-permission-check \
--no-check-certificate \
--url https://redmineserver.ourdomain.tld \
--key [randomstuff] \
--allow-override all \
--no-account-notice \
--default-group Support

I still get though the following error

"permission denied. Command output: Request was denied by your Redmine server. Possible reasons: email is sent from an invalid email address or is missing some information" 

This is my currentn setup

Environment:
  Redmine version                3.3.1.stable
  Ruby version                   2.3.0-p0 (2015-12-25) [x86_64-linux]
  Rails version                  4.2.7.1
  Environment                    production
  Database adapter               PostgreSQL
SCM:
  Subversion                     1.6.11
  Git                            1.7.1
  Filesystem                     
Redmine plugins:
  accept                         0.0.2
  issue_mail_with_attachments    0.1.0
  redmine_autoclose              0.0.4
  redmine_close_button           0.0.8
  redmine_default_assign         0.6
  redmine_gc_sync                1.0.0
  redmine_mail_reminder          3.0.0.0001
  redmine_pretend                2.0.1
  redmine_tweaks                 1.0.0