I had a few collections to turn in (butterflies, rainbos, foxes) and I went to turn in the first one, with the foxes. When I clicked turn in, it turned in my rainbow and butterflie ones instead. So I clicked turn in on the same collection 3 times to turn in all of them.

Hope that makes sense.

It has always been like that.

You have a random chance at getting any of the decor pieces in a set. It's not guaranteed a fox, foal, double rainbow etc.

The game turns them in from the bottom to the top for some reason.

Oh I know I just couldn't remember the collection number. So the different sets of 4 possible animals are one collection. I mean that I click the button on #4 for example, and it turns in the ones from #10, then #7, and so on.

I know it's random which specific animal you get, sorry I worded it weird.