The only way to get good depth of field with high magnification is with focus-stacking, which can be tricky, but worth trying.
I had this lens for my Canon camera before I switched to Sony, but it developed a fault where the iris didn't stop down fully sometimes. Laowa asked me all sorts of questions before they would tell me how to get it repaired, which involved posting it back to China. I couldn't be bothered as I decided to switch to Sony at about the same time, and I just threw the lens away. Laowa's customer service is appalling.