polygons' ID different from @data ID in a spatialpolygonsdataframe

Question

I loaded a shapefile in R using readOGR and I named as data.map

I can see the shape pretty well by using

plot(data.map)

The issue is that polygons' ID (the ID of the plot) is not the same with the @data ID. What I mean is that, when I run:

plot(data.map[2, ]) 

and then run

data.map@data[2, ]

the polygon that is drawn in the plot is not the one that the data row refers to.

Answer 1

I do not know if i can delete the question. I found the solution. the problem was that after a merge procedure many of the @data rows were deleted and that resulted to have the ids messed.