A Game in Steam what in steamgifts not exist

Probably means it was given away for free at some point so you can no longer make a giveaway for it.

its free game bruh

you bought this bundle http://store.steampowered.com/bundle/2129/ and got Shiplord as a gift? ʕ•ᴥ•ʔ

It was free so you cant give it away.
See this list.

Beta keys, guest passes, coupons, and free games should not be given away.

https://www.steamgifts.com/about/guidelines

this game isnt free guys normal price cost 2.99€ and now on sale 0.50€

Any game which has been free in the past, is no longer available to give away on the site. If you really want to give the key away, you can drop the key in a forum post and some -ninja- will collect it gratefully!

That goes for a game that costs £30 to a game that costs £0.20, if it was free before, its unavailable to gift to anyone through a giveaway.

It was given away free en masse previously, so even though your copy was paid for, the game has been disabled here to avoid leveling abuse from those that did get it free.

I won shiplord and about 2-3 months after that it was given away somewhere like gleam. Sorry man it's worthless now whether you bought it or not. Gift it to a friend or drop it in the forums. That's what I do :3

You might want to read the FAQ & guidelines. If you have any more questions regarding the rules there, try searching the discussion board.