Weird Sprite collision

Hello! I’ve been trying to make 3-match game, and I used sprites for each gem that uses a simple 1px thick box collision. I also added physics to them in the blueprint I made

Now in the level, I made a nice “For” Loop to fill my 8x8 gem board. When I run the game, it’s all good, until I see THIS collision:

What’s going on? Why are they going inside each other?
Here’s my sprite collision:

Well, I pretty much made the thickness more than 64px and it kind works now!

Thickness worked in my test too!