I bought two West Elm Tillary sofas a few years ago for my apartment. I loved them and had no issues. When I moved to my house, it was a different story.
In my apartment the sofas were right up against the wall, but in my house the sofas are in the middle of the living room. The top section of the sofas do not attach to the bottom--they only have a little grip on the bottom to stay in place. When anyone leaned back on the sofa, the grip did NOT keep the top in place.
I had many people fall over when the top did not stay in place so I had to come up with a way to keep this from happening!
A friend of mine helped me come up with the design. We cut plywood to size, sanded the edges down, and used hex bolts to screw the wood board into the base of the sofas. When we drilled the pilot holes into the wood and sofa base, we did have some batting come out and get twisted but this was not a major issue.
I have not had anymore issues with the sofa since adding this fix!