Why can I still enter giveaways for this game I own (Yes I have synced my account since)

Sync you account
http://www.steamgifts.com/sync

Well I have not been helped.... POLE and bye!

Resync

sync your account

EDIT: lol

The collections seems to be a problem in general. I know I can enter Deus Ex collection, King Arthur, Space Marine etc even though I own all of the items.

I have written to support and they've said that the issue is being investigated.

Whoa, first 3 comments, no one even read the title? You guise are disappoint.

The problem is that the dlc doesn't appear in your list of games.

DLC doesn't appear in your sync list so it appears to Steamgifts like you don't have the Collection.

Edit: Ninja'd

A lot of times collections/bundles aren't put into the system of possible owned games because you don't technically own eg: The Binding of Isaac Collection, you own The Binding of Issac, Wrath of the Lamb, and the Soundtrack. I may be mistaken but I'm pretty sure things like bundles and collections would have to be manually put in because some will actually say you own it like The Magicka Collection while others won't.

If you have the game why you are worried about it? Just don't enter, easy solution for you.

if you buy a collection its some times messed. i can still enter arma 2 co when i own the 2 games seperatly

I get the same thing with a ton of DLCs, it's kind of annoying because I have to remember which ones are glitched. I've also been able to enter for a few I didn't have the base game for, but I removed the entry after realizing my mistake XD.