I'm completely new to GIS and this is a very basic question about editing existing shapefiles.
I am working off an existing shapefile which was digitized (by a colleague) so that polygons represent building cover. The shapefile contains information about the land use type and area. I am using QGIS to edit the shapefile.
Now, I wish to add/remove/edit polygons to improve accuracy as the extent of building area has changed a lot recently.
However, when I add new polygons into the shapefile (by digitizing it using an updated basemap), they are not added into the same polygon class as the earlier shapefiles, even though I input the right LandUse type (i.e. Buildings) in the attribute form. Each new polygon seems to create a new LandUse category, even though they're all namd "Buildings".
How do I ensure that any new polygons I add are added into the same LandUse class (all previously created polygons are in this "Buildings" class)?
Thanks in advance for any help on this.