Difference in sales deed in first owner and second owner

We bought a row house bungalow from NRI and became second owner of the property. Our sales deed mentions total plinth area and land area of the property, however the sales deed of the first owner only mentions the plinth area of the property and undivided share of land. We bought this property in 2005 and the original owners bought it around 2001/2. On basis of our documents we had recently updated our property card and Index and was verified by municipality. Our Neighbours have raised a dispute in court that the land area is not mentioned in the fist owner sales deed hence the only part we own is till the plinth area and the verandah land is not ours and we cannot use it and rather it should be open for public use. The overall society plan also shows the land with the our property block. The old owners are no more in this world and being a old property no documents further can be traced. Do advice how can we resolve the court issue and justify our legal registered sales deed