What Causes Double Vision Post Cataract Surgery?

I have had cataract surgery (traditional) on both eyes. The left eye did fine. The right had to be redone because the vision was not good after. Doctor states there was a problem with position of lens and a tear was made. After second surgery on right, the moon shape of light was removed and a great deal of floaters were removed. However, my vision was not has good as before. I was experiencing double vision. When I went for fitting for prescription glasses. I was told I might need a "slab-off" prescription, but they were going to try regular lens first. My concern is that my vision is worst instead of better after the surgery. I ask why my right eye was giving me so much trouble and was told because I had more stigmatism in the right. I did'nt experience any difference in my stigmatism before surgery and did'nt have any correction done for stigmatism during the surgery.