I am convinced that you bought an inversion table of insufficient quality and that it was not fixed properly. First of all, in order to understand how to fix it, please look at the manual that comes with every table of this type. If you can't find the answer there, take a look at the tips from the guys above. I've never had to deal with this because I've been a regular customer of
https://www.proinversiontherapy.com/best-inversion-table-reviews/ironman-gravity-4000/ and their tables were completely satisfied with their quality and fixation. It is thanks to the inversion tables, I got rid of my back pain which had been bothering me for several years. In general, it's a wonderful invention, isn't it?