I can only guess without seeing it one of two things may have occured..first take a flashlight and inspect the fixture where the center pole was attached and see if maybe a screw or some hardware has loosened and fallen out ,if that looks to be intact inspect the end of shaft to see if the structure or bearings it used to rotate on have simply worn out,thus needing to maybe replace that part"suggest checking your local ace etc to see if you can match the old one or replace the entire lazy susan unit