I used to update my catalog via PC. But I'm on my Wii U right now. it's showing my catalog as completely empty but it shows my total collected items under My Characters. Is it possibly because I'm on my Wii U?

Hmm, that's bizarre! I can see your catalogue perfectly well - it shows, for example, that you have all of the items in the Artwork category except the Amazing, Perfect and Quaint Paintings.

Are you sure you're looking at the catalogue for your default character (Kitty, not Diego)?

Yes. I starting checking things off again.

Had you been inactive on ACC for a long time? Your catalog may have archived. Modmins can usually fix this, though I don't remember if that still works or not.

Yea I have been inactive because I stopped playing New Leaf for awhile. I'd say a couple months at least.

I've manually rechecked everything. I'm still just wondering what may have caused it.

I'm guessing it was due to your inactivity.  Catalogs archive if a user does not log in for a specific amount of time (although I'm unsure what that amount of time is).  I know the mods used to be able to unarchive it fairly easily, but I'm not sure if that is still possible.

Ah. It's alright. It's all back to normal.

I have this issue as well...probably due to inactivity.  Who do I contact about fixing this?