I've started a new game and have gone back to check on all other tribes, now none of them are getting any. Even my initial tribe that got a bunch before.

We have never seen that happen in months of testing. It could be a glitch that we've never seen. You could try reinstalling your game (without uninstalling first). If you want to be safe, you could back up your savegame files first, following the procedure in this post.

I did that and nothing. Not only that, but when I tried to restore my games, I found that they were all gone.

So, now no saved games and still no seashells.

Reinstalling should not have deleted your savegame files or backups. Did you uninstall the game, because that might have deleted them?

No, I just reinstalled the game.

The mystery is solved, though. I restarted my computer and now it works fine...My backups are still out there somewhere, though

Are you getting collectibles again?

I have a totally different collectables problem.
On the first game that I started. I have been able to pick up butterflies,pebbles seashells and beetles.
But on the second game I have been playing I can't pick up butterflies or beetles. I do perfectly fine with the pebbles and the shells but not with the butterflies or beetles.
And what aggervates me the most is some of the collectables are few and far between.
I get more black and white butterflies or blue ones, and I get the ladybugs and the red beetles a lot, which I understand that this is part of paying attention to the game, but I have been seeing the beetles and butterflies that are hard to get and I can't pick them up.
It is so frustrating.
Is this a glitch in the second game or what?

Yes! Finally. I don't know what the problem was. I tried to be patient, but then it became clear that something was wrong.

I still don't know where my saved games went, but that's ok. At least I actually have a shot at finishing the game now!

Thanks so much for all your help.