About favorites and broken (or possibly missing manga)

I added Chapter 3 - Basement Labo 2 to my favorites, but I don't see it in my favorites. I mean, I got the notification that say "You have successfully added Chapter 3 - Basement Labo 2 to your Favorites", but it isn't there.

Also, what happened to Shiro Kuro Royal Ch 6? I mean, I did favorite it, then it disappeared.

Just wondering what's going on?