Rights of bonafide purchaser of land

On 15 may 2006 an agriculture land was purchased through power of attorney. at that time two brother were the owner of the property.both of them were unmarried and have no sons.they sold the property through poa by their person to us.we did the registration of property at registar office and paid stamp duty.after 1 month land got on our name.but we didnt given notice regarding sales deed in newspaper,that time it was not common. after 10 year someone approached my father saying that it is his ancestrol property his uncle sold the land doing fake sign and all.after inquiry we came to know two person to whom land was belonging one of the person was died few months ago.but during time of purchase we find poa OK after consulting with lawyer as it was notaried by other lawyer.SIR THIS IS THE CASE OF CHEATING WITH US DONE BY ONE OF HIS UNCLE.WHAT TO DO ?AFTER 12 YRS WE SHOULD GO FOR SETTLEMENT? OR FIGHT CASE?IF HIS PART IS LEFT IN LAND WE ARE READY TO GIVE HIS PART OR THE MARKET VALUE OF THAT PART