Shop and Game items won't combine

I've noticed that ever since the May forced wipe, the game spawned resource items won't combine with those purchased via the Shop. I have it set up where players can buy ore, metal fragments, stone, etc with diesel. When they buy those resources and then obtain some elsewhere in the game, they cannot combine them. I've placed both on the ground and did a debug.lookingat, and the prefabs are identical. I don't immediately see the culprit but wanted to bring it to your attention to see if you have any thoughts.