Is it in full sun? When the heat is bad, I think they do better with at least some shade. I assume it's watered often enough. And I think a lot of plants are having trouble lately. All that rain and cooler shadier than normal weather, then bang! Suddenly no rain, sunny all the time, hot summer temps and the lush growth from the rainy period is in peril. Too much change too fast, some plants can't take it. I've lost some plants that were new small plants...just couldn't take it!

The leaves in your photo might show Leaf Spot disease. The symptoms are brown spots often surrounded by a yellow halo. Under wet conditions spots can run together. The disease can be caused by either bacteria or fungus. The most organic treatment is spraying with a baking soda solution (a tablespoon of baking soda, 2 1/2
tablespoons of vegetable oil, a teaspoon of liquid soap, not detergent,
to one gallon of water), or neem oil
(do not use when pollinating insects including bees or other beneficial
insects are present). Baking soda may burn some plant leaves. Spray
only a few and then check for a reaction before applying applications
every two weeks.

Another leaf in your photo appears chlorotic (yellow with green veins), so the problem could be NUTRIENT DEFICIENCY. Both magnesium and potassium deficiency can also produce dark spots. Look for a water soluble MICRONUTRIENT fertilizer for quickest results.