Registration of Unfinished and incomplete FLAT and Legal Remedy

I lived in a rented house and house owner wanted me to vacate their house by December 2021. So, I looked for a ready to move in and ready to live in Flat in Kolkata. Through online I found an agent/broker and he introduced me with a Promoter/Developer (Son and Father). After a meeting with all of them at the end of November 2021 and getting their verbal assurance and promises of giving me a ready Flat within a month I made an advance payment to them on first week of December. After that they did not issue me Allotment Letter or Agreement for Sale in spite of repeated reminders given to them. By false promises and assurances they continued to grab money from me but did not complete the Flat for me. They could not complete the Flat by December 2021 or even in January. By that time I had to vacate my rental place and I did not have home in spite of I paid full amount to the promoter. By false promise they grabbed full consideration amount of the Flat and also completed the registration of Deed of Conveyance of the Flat in my name on 31.02.2022 but Flat was not in living condition with all facilities and amenities. They did not pay me rent as promised. They did not complete the Flat as promised. Months after months gone. Then they started threatening me not giving Flat or refund of Money. I lodged complaint before Municipality and the Police Station. Soon after that they handed over keys of the Flat to me but Flat is not in living condition. So, they could not give me possession certificate too. They do not have CC or OC from Govt. office. Police Registered FIR followed by Charge Sheet against them on August 2022 for cheating me. By that time also Flat is not in living condition. I filed a consumer complaint before the District Commission in September praying for refund of money with compensation and remedy with interest. But District Commission remained biased to promoters from the beginning, advocate commissioner was not appointed for getting the report, and finally dismissed the petition stating that I am not a consumer and there is no deficiency in service. How can I get the remedy and relief, and can I really get justice in this case?