Problems in drilling borewell due to rock layer in Anjanapura, Bangalore, Karnataka

I stay in Anjanapura in Bangalore south and we already have two bore wells in our apartment which were dug some 5 years back to a depth of around 400 feet.  Recently the water yield from these 2 borewells have been reduced and is not able to meet the requirement for people in the apartment.
So we decided to dig a new borewell few days back. The borewell complany started digging and was expecting water at around 800 feet but were still encountering rock layer without a single drop of water. So they ultimately went to a depth of 1000 feet but still the layer of rock continues. Ultimately they stopped the work.

Please suggest on what we need to do now? Should we bore further down on this borewell? Is there any hope of getting water from it?

S Patel