Why is 404 displayed when I open my favorites

As title，Why is 404 displayed when I open My Collections？

and What is the love-mark above the picture used for，thank you

"My Collections" - available only for paid supporters.

What is the love-mark above the picture used for

If you mean this one. It's just a type of reaction.

You can view images you reacted to in your profile - go to Images and click My Reactions