I would say take apart all the long bolts a have a look and follow the directions one more time and reassemble it. Now that you have an idea of what direction it was wrong, pay close attention when putting it back together. I am trying to build another one, I have all the parts ready and the table built so maybe today. But I have had to take the middle apart before myself. I think sometimes the fit is just too tight and when putting it together again loosens up the bolt holes a bit or something.
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