[Resolved]  Gujarat Housing Board — Advance payment of all the installments

I had purchased one Flat at Gujarat Housing Board by Re-sale. I want to get documentation of this flat. So had paid all the dues to Gujarat Housing Board in advance. After payment of all the installments in advance I again asked by housing to pay the regular installments. My father had regularly paying the installments. Also Housing company had asked to pay something like all the installments amounts. Once again eventhogh paid once all the installments, regular payment of installment, in second time we had paid full installments in advance. Even after that also regular installments are asked by Housing board and had not cleared the balance due. What can be done in the case?