One of the two wire 'restraints' that enable and safeguard the opening and closing of the tabletop to accommodate the insert was frayed apart and so useless.  My guess is that it became jammed in the sliding mechanism and snapped. It was this way when I was opening the box. I've assembled the table anyway and will use it as such. It's too much trouble to return. It is an irritation and will be a real nuisance when putting in the insert. Apart from this issue, the table is fine and what i expected.