I followed the tutorial to do a project to buy something from the store and get into the backpack, but I seem to mess up. When I click to buy, the first item can be added to the backpack, but when I click on the second item to buy, he can’t join the backpack, although he has already joined in the background, when I close the backpack, open it again, the backpack does not show the items that should be there, at this time, I click to buy, the grid will become more, how do I change to fix these problems? I hope someone can help, thank you.
