Q.Peach Tree Dying
I have a new peach tree. At first it was doing great and now the leaves are yellow and falling off and the fruit that were present are all gone. My neighbor’s tree that was planted and bought at the same place and time and is doing great. What did I do wrong and can I save it for next year or should I trash it and start over?

It sounds like it may be in shock. Increasing water to the plant will help. These articles will also help:
https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/watering-newly-planted-tree.htm