For reporting behavior or actions on any FAF monitored medium use: https://www.faforever.com/account/report

For appealing actions done to you:
Write a message to Giebmasse on the Forums here. You can do so by clicking the chat bubble next to your profile picture, going to "see all chats," and then typing his name.

You can also go to: https://forum.faforever.com/groups/global-moderators
and find Giebmasse. Once you find his name, click on his profile and hit the chat button.

Understand the Moderation Team are volunteers and will respond to your inquiries within a few days. If they do not, feel free to send a followup message to them. If that still fails, contact me and I'll relay the concerns.