Certified GKH Gardening Expert
Unfortunately, your photos did not come through. I am unable to see the damage.
If the soil was not tested prior to planting, and it was fed on top of sufficient nutrients, then it could be due to high nutrient content of the soil. I would test and make sure.
Once you get some results, then you can begin to correct the issue. Unfortunately, without a test, it will be hard to say what is going on.