Dimension accuracy problem

Hi All,I have an Elegoo Saturn and was printing just fine until yesterday, I didn't see an object that fell into the resin tank.When I tried to run another part, the build platform ran into the part, and moved the swivel mount. I had to changethe FEP, no problem,and re-zero everything, but now my prints are quite off in dimensions. A part that was supposed to be 76.2 x 76.2mm nowmeasures 74.5 x 72.36mm. Did something inside get shifted off, and how do I fix it?Any help?Ken