Fruit dries up but stays on branches.
What Causes Peaches Not to Ripen?
Certified GKH Gardening Expert
Did your fruit develop brown spots before mummifying (drying up)? If so, I think your tree might have brown rot fungus - this causes peaches to mummify on the tree.
You can read more about brown rot fungus, and the recommended course of treatment, at the following link: