Why am I having blurred vision since I started taking Atorvastatin?

Because it is a serious side effect of the medication:

Stop taking atorvastatin and call your doctor at once if you have any of these serious side effects:

unexplained muscle pain, tenderness, or weakness;
confusion, memory problems;
fever, unusual tiredness, and dark colored urine;
swelling, weight gain, urinating less than usual or not at all;
increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, ****blurred vision****, weight loss; or
nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects of atorvastatin may include:

mild muscle pain;
diarrhea; or
mild nausea.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

https://www.drugs.com/sfx/atorvastatin-side-effects.html

Take care,