Can govt grab the house

I purchase a plot of 100 gaj in 2015 and got the mutation (dakhil kharij) also. And I made a house in that plot for living my family. But after one and half year govt declared that plot as Govt land giving reason that plot belongs to SC person and DM permission was not taken before sell. Further I want to say that person deceive me and u taken loan also on that property. If that plot belongs to SC person then how the Tehsildar did the mutation. Please clarify that is residential plot and I have given residential stamp duty also. Please help me I belongs to Uttar Pradesh.