I have a potted Glenn mango tree, about 1.5 years old. It recently flowered for the first time and everything looked great. Then, about a week ago, half the tree began to wilt and the flowers and leaves started drooping. The other half still looks healthy.
Mango Tree Wilting
Certified GKH Gardening Expert
This could be due to watering issues or poor drainage.
There are some specifics for growing an indoor Mango Tree.
It is also best to cut the first year flowers from a new Mango Tree to help stimulate good growth in the plant.
Here is an article that will help refresh you on the care requirement.