Supertech — No construction No possession No intimation

I've booked a unit in 2018 and possession was due in July 2019. Now it's 2023 and here I am, still waiting. Neither there is a sign of construction nor any intimation from the builder. I've even tried there every single number. I'm paying EMIs, losing my hard earned money and it's totally worthless. I'm looking for a solution. It's financial as well as mental harrasment. Is there any complaint group against them.?? Now I want to take some legal action against them.