Land dispute - Wants to know consequences and responsibility

Hi, I want to no consequences & impact from below issue. This issue is related to land which was sold by my grandmother in 1985. At that time my father and uncles were present and involved, now no one is more) This land originally was agricultural land, in the view of sale this was converted to NA, by us (party A) at that time the planned road was 10 feet, which was shared with another land owner (we will called Party B) this sharing agreement was done on 5 rs stamp paper (we have photo copy) then we did NA and sold to party C. in 1985, since from that time party C is owner and using it (they have built house on that ) Now the question arise from party B, they said we had agreement of 15 feet road, and they now in position to filed legal notice on Party C. for asking the 7.5 feet road, and party c is diverting it to us as we were seller, now party c is not ready to keep 2.5 feet for road and drainage line. Whereas at that time there were only 5 feet road kept, and as per our knowledge this was mutual understanding happen at that time, as in between rules changed, when the party B wants to have NA plotting of their land (rule to have 15 feet road). As per this we sold remaining plots with 15 feet road (i.e 7.5 ft as our share this may have again agreement … but not sure) Now my question is : - Are we still responsible for this? if yes how . - What are the legal consequences and how we can manage this. - One more are the party c have right tosay that they have full ownership as sale did didn’t talk about road and space to keep. - If any mistake happened at that time by our parents then what will be scenario.