Hi,

I have a 4-5 year old Mango tree.
For the past 2 years or so, I am fighting a disease which causes black spots on leaves and fruit stems.
This year the tree barely managed to produce any new leaves, the fruit stems dry out and the small fruits falls falls.

What could be the cause ?
Is there a way to restrain the disease ?
Here are some photos that might help

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Image 3: