you probably need to open a support ticket, but before you do, I would suggest you print the calibration form file that @JoshK has posted to the forum somewhere, search for it. He also has a great spreadsheet that calulates fine tuning percentages.
Using a dial caliper, you’ll want to measure the actual sizes (x,y, and z) of the blocks and separation of the blocks in the file. If all of this just started with a new tank (and your mirrors did not get dirty while swapping it), then it may just be the z-offset needs a bit of tweaking.