The middle seat of my ESKILSTUNA couch started sinking, I found the screw holes that hold the wheels were completely worn out. Because of that, the seat was sagging more and more over time. I created a 3D-printed support that can be installed next to the original wheel mounts—or you can remove the wheels entirely. It is printed with a vertical grid pattern so it can handle most of the load more effectively. Sharing this here in case anyone else has the same issue and wants a simple, sturdy fix.