Liminos Technology — Builder gave Fake Promises before Paying Amount to Flat Builders and Developers Terrible quality of Flat

I have booked a flat in Virar (Nagarpada), from Gzm (NG) Builders, project name is Park Phase III.
During booking all basic amenities were promised and like a politician big promises were made and charges were levied accordingly. The Property is not even a year old.
1) We were promised BMC water supply and it’s over 4 months that we have booked the flat and many people have even moved in, but till now there is no water supply. Water is supplied using tankers (we all know where these tankers get the water from). Some residents have complained about a slimy layer of yellow muck deposits on the utensils on usage of such water. Residents buy canned/bottled from surrounding shops as drinkable water.
2) All the flats right from the top floor (7th) are leaking heavily.
3) Majority of residents have received flats with broken tiles and Kitchen platform cracked
4) All hinges and screws are rusted
5) Ceiling is unlevelled.
6) Majority of residents have received flats with irregular pipings
7) There is no security and the garden in our premises is a "adda" for surrounding slum dwellers.
This is just tip of the iceberg. Residents have complained to builder but no response is received. There is no site engineer to complaint and the site/sales incharge changes regularly.
The worst part is the Building has received an Occupancy Certificate, so we can just assume about the Builders hold in BMC.
I am in a terrible mess. Buying a property at this young age wasn’t easy and now I just can’t think what will happen.
I plead you for all the support and co-operation for obtaining justice.