I have three DLC's that I bought or claimed recently and they've all been added into the "Owned games" and "Recently added" sections as "Unknown games". Nothing will remove them unless I hide them. It never used to do this either, but I assume after one of the somewhat recent Galaxy updates that you broke something...

The DLC's that I've gotten since then are as follows:

The Dungeon of Naheulbeuk - Splat Jaypack's Arenas

Othercide - Dressed to Kill - Cosmetics Pack

Pathfinder: Wrath of the Righteous - Paint of War

I'm really getting tired of stuff just not functioning here at GOG. DLC's should not be added into your library as unknown games. Pathfinder was just added today when I claimed the free DLC. The other two have been there for weeks with no way to remove them without hiding.

I went to put in a support ticket, but you're immediately greeted by the following message:

"IMPORTANT NOTICE! WE ARE CURRENTLY EXPERIENCING HEAVY SUPPORT TRAFFIC THEREFORE, RESPONSE TIMES WILL BE HIGHER THAN USUAL. WE APPRECIATE YOUR PATIENCE AND UNDERSTANDING."

Oh, gee, like that hasn't been an ongoing thing for years now. I wonder why that could be? Maybe because the store is dying and GOG is understaffed and overworked? I didn't even bother putting in a ticket because I don't care anymore. I'm just done.

I'm really regretting the day I ever started spending money on this store, and believe me I won't be doing it again. It's not just this one issue either, it's a combination of things that happen through no fault of my own that suggest that GOG isn't even able of functioning at the most basic levels at times. That's it for me. I'm throwing in the towel, because I just can't do it anymore here.

I don't blame the GOG staff, because you can only do so much when you don't have the resources or manpower needed, but that's really not my problem now is it? GOG as a store just stinks, objectively speaking, and it's been that way for a while. And does anyone actually see it getting better, maybe ever? I sure don't.

All DLC's or just these ones?

It sounds like a configuration issue with GoG, where the parent/base game and some details are written wrong with either the site database, or incompatibility details between Galaxy versions.

Hmmm, if you want, try removing your galaxy cache information (probably %appdata% somewhere) and re-register your username with galaxy and see if the problem goes away.

If you change your mind about giving up...

Exit GOG Galaxy then load https://www.gog.com/user/refresh in a web browser while logged in. There won't be a confirmation message or anything.

If that doesn't help, exit GOG Galaxy completely again, then move one of these folders to the desktop, and restart GOG Galaxy afterwards:
C:\ProgramData\GOG.com\Galaxy\webcache
C:\ProgramData\GOG.com\Galaxy\storage

If that doesn't help either, while GOG Galaxy isn't running, delete the above newly created folders and move back the old folders from the desktop. Then open a new support ticket by repeatedly telling the chatbox it's not helpful after every suggestion. After that, you may have to wait weeks to get a response. That's why you'd ideally open the ticket the moment the problem occurs; you can always reply to say the problem has been resolved afterwards.

Merry Christmas.