Municipal Corporation Of Navi Mumbai — Property on name but still do not have possession

Address:

4/1939 sector 1 shivcolony Airoli Navi mumbai 400708

We have Plot on my father's name Mr. PANDURANG BALKRISHNA DAREKAR
We lost original property documents, and plot is using illegally by another person since approx. 1996, we are still receiving property tax but amount not paid till date as plot is not with us, I want to take over this plot, kindly help/suggestion

Property details as below:
AI[protected]
AIR-AIR-1943