Partition of land from second owner

Sir, my father purchase agriculture land 1acer from my relative he is paid money to him and make affidavit not register. Land owner haveing 4 acer in that father puchase on 1 acer.The land is connected with our another plot so father only purchase 1 Acer from owner and remain 3 Acer was owner name , after 4 years owner sold 4acer to another person .At time of making document he leave 1 Acer land but they wrongly mention our neighbours name. My father talked with second owner they are ready for mutual understanding but they are given option 1.give money for 1acer 2. Partition of land of only 1acer But my father use this land for mango tree and cahew tree so our father and my family member not want to sold this property . The second owner is told that the partition of land is not possible because the land is nispra land on equal portion can be devide. And if he is not ready to sign for document partition process what we do? Kindly advise for partition of agriculture land or file suit My email ID anilrambade2011@gmail. com