Illegally encroachment

Dear sir, I have a piece of land measuring point .21 acre by acquiring of whole land purchased from my neighbour's relative by proper valid documents like Registered Sale Deed, mutation and computerized jamabandi.My name is also rightly recorded in Record of Right(ROR) in Revenue Department of Manipur with exact area of point .21 however trespass / neighbour arbitrarily questioning me about boundary dispute and claiming that our land area is not about Point .21 it should be point .18 less 3 point .. it is totally baseless allegation.whenever we are trying to demarcate our land for fencing,she often obstruct me to do the demarcation.we could not proceed it..and the I written complained to the Sub-divisional officer(SDO) of our jurisdiction to intervene the matter.we have done hearing many times in the court of SDC.but the neighbour didn't co-operate the order of SDC to demarcate our land instead she stand his own opinion and shouted ,arguing us even the official team also.The demarcation was not concluded...fail.... My questions (1)Has SDC right the power to Demarcate the disputed land by using police after the case resolved? (2)If SDC couldn't solve my problem, where should I file this case further? (3)If the part fail to attend the hearing many times after summon by SDC,what action should be done by SDC against him/her?