SG Estates — late in possession and registry

Hi,
I'm the owner of flat c-1501, sg grand, rajnagar extension.
The builder promise me to give possession of my flat till august last but till now no work is done neither house work nor the check visit.
I'm not in that condition to pay the rent of the flat where i am temporarily living and the bank emi simultaneously which cost me around rs. 40000
Please look into this matter.
Your quick response is appreciable.