First check if the lead screw is deformed. If there is no deformation, then see if there is any problem with your bearing housing. Use a dial gauge to hit the table at the fixed end, and the beating should be controlled within 1 wire.
Then the lock of the nut seat should use the diagonal lock method, and it can not be locked at one time; first fix it, then push the work table by hand, then loosen the nut and fix it;
This way, two or three rounds are locked again, and it is best to use a torque wrench.