Government gifted land

1. my father bought agricultural land in the year 1990 . He got Patta from the Revenue Department , Paying Agricultural Electricity bill, Name is Reflecting In Village Settlement Records 2. The seller sold the property by registered POA (irrecoverable) holding in his name, he got the Registered POA (irrecoverable) in the year 1986. 4. PTC had also erected high tension tower for power lines in the year 2012 and paid us compensation for cutting trees from our land some village people have started claim that the property was gifted by government for their betterment in the year 1974 which the Power Agent fraudulently got it POA (irrecoverable) registered by saying that i will get loan to you ,There Is Thumb impression of all the original owners. 4. I have heard they have appealed to the District collector to look in to the matter. that they did not know how their land got sold to us, as they gave POA to the seller for loan purpose, 5. It might be true that the some part of land was issued by government to them in 1974 7. it is clear that they are trying to grab our land back ,what shall i do now as it has been 25 years since we bought it ?.