What can I do if my builder delaying the registration process of flat even after paying token amount?

I have purchased flat last year but it was hold in registration as it comes under grampanchayat due to that loan cheques were cancelled and bank said to apply new loan instead of reprint cheques. Sir I have also paid emi of home for the loan 4 months,bank said emi amount also will not come. Now they are applying for new loan Same bank and builder delaying and not answering. Please suggest what I can do if I proceed with legally as I have paid token amount.