Flip your sofa over. Look for cracked corner blocks or webbing that has pulled away from the wooden frame.
Most modern sofas are held together with staples and dowels. Over time, those joints wiggle loose. Wood glue is fine, but DAP construction adhesive has a rubberized grip that absorbs vibration—perfect for a sofa that gets jumped on daily.
It is highly likely this is either a typo, a specific internal model code, or a mix of different terms.