Is it legal for a neighbour to extend their metal roof (inclined) to a large area over my terrace

A neighbour to my residence in Kolkata has extended a metal roofing, which is inclined, to a large area hovering over my terrace in way that rain water slides down the roof, down-pouring large volumes of water in the middle of my terrace. Also, is it legal for them to open a window on their wall adjoining my terrace in the direction overlooking my terrace? We took advise from an informal meeting with the ward councillor and his team to build a wall and we built a 14-feet wall till the roof. But now the ward councillor and team are asking us to break a part of the wall as it seems it is illegal to build a wall more than 8 feet. Instead he wants us to settle the matter with my neighbours through dialogue, adding that both of us have to stay in that area so better to maintain good relations or else it will be difficult for us to stay there. However, they didn't ask my neighbour to abandon their roof extension and window construction as they have apparently politically aligned interests. Could you please provide us some legal guidance on how to handle this situation?