Our recently planted Acer, ( golden colour) has brown edges to the top leaves and they are beginning to curl up,the rest of the
plant is fine, at present.
Certified GKH Gardening Expert
Fungal infections are very common in Japanese Maples, but are not difficult to cure. This article will go over fungicide use: https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
This will help you to care for Japanese Maples: https://www.gardeningknowhow.com/ornamental/trees/japanese-maple/japanese-maple-care.htm