Whose Mutation stands

Sir, My father purchased property 32 yrs ago & died few yrs later. My mother's name was mutated by the CIRCLE OFFICER in register II, 9 months after my fathers death. Her name is till date in the register 2 & revenue receipt in her name. 4 yrs ago when we went to take stock of our property it was found somebody else is having possession on it. After enquiry it was found that my then retired grandfather gifted this property to my aunt 27 yrs ago stating that he purchased this land BENAAMI in my father's name. But this is not true as my fr had purchased it on his own. On findings i got knowledge that my aunt had challenged my mother's mutation in SDO court in 1989& the SDO ordered aunt's name mutated by cancelling my mother's name & issue a Shuddhi Patra. But this was never received by us. Owing to this order My aunt (wife of govt officer) got her name mutated in register ii & accepted & acquired this gift & later on sold this land to another person who has his name mutated. My mother's name is still there in register ii i.e mutation is still existing as per RTI & also we are getting revenue receipt, but at the same time another MUTATION is also continuing for the same land & they are also getting the receipt My question is - 1) Can there be 2 mutation for the same land, if yes, then who is the real owner of the land ? 2) Does SDO has any role in cancelling mutation irrespective of hierarchy of CO - DCLR - COLLECTOR 3) We are not in posession of the property what will be outcome Kindly suggest the correct legal ways what to do ? Thanking You , Ajit