Presumably one of them has been chopped down. Presumably because it had some problems.
It is not surprising that these trees have problems. Knowledgeable people have said that the root system of a banyan tree is about the same size of its crown, the part extending upwards from its trunk. Just look at the pitiful size of the hole around the trunk. The roots of a tree needs water, air and nutrients to survive. Pretty much all the roots of the tree is buried under heavy concrete. Where is it going to get its water and air and nutrient from? It is a miracle that one of them is still standing. For how much longer?
We are murdering these trees.