I have a shapefile with small polygons, that I need to merge into larger ones. Merging should be by a specific variable, conparid, which is available for any polygon. I am trying to use the 'Dissolve' and 'Pairwise dissolve' tools, but receive a message 'WARNING 000117: Warning empty output generated'. I successfully ran 'Repair Geometry' and 'Check Geometry', but this did not help.
Eventually, I simplified my dataset to include only two polygons, which I am trying to merge. Please see the screenshot attached. I wonder what could be wrong, and would appreciate any suggestions.