The position of my background is moving. All of the positions and sizes are in scale and the anchor point for all of them is set to (0.5,0.5). (The arrow is not moving, its the grey background that’s moving.)
I assume you are talking about GUIs? It’s better to give us too much information rather than not enough…
Are your screen sizes different for Studio and for in-game?
If so you need to make your UDim2 values compensate for different screen sizes for all users.