Servers included: pub1.ibisgaming.com, gg.ibisgaming.com, zm.ibisgaming.com, wcs.ibisgaming.com, gopub.ibisgaming.com, ns2.ibisgaming.com

As long as you're in one of those servers, you should have a reserved slot. All that means is that if the server is full, you can bump someone without a reserved slot to make room for you.
If that is not happening then there is an issue.

Zero would be the one to look at your account info and see what's wrong. To speed things up I would post your steamID in this thread so Zero can make sure it matches the reserved slot list.