Support for Nagios products is available through our support forums:
https://support.nagios.com/forum/
In the top right pane of the support forums click the Register link:

Agree to the registration terms.
Populate all the fields and click Submit.
Follow any remaining step that are outlined or emailed to you.
New users will need to wait for their first two posts to be approved before they appear. This is an anti-spam measure and we appreciate your patience.
Please follow the guidelines in this article:
Support - How To Get Fast Resolution To Your Issues
Article ID: 442
Created On: Mon, Feb 8, 2016 at 9:39 PM
Last Updated On: Mon, Feb 22, 2016 at 10:50 PM
Authored by: tlea
Online URL: https://support.nagios.com/kb/article/support-forum-access-442.html