Before you delete any buildings or features make sure you are using the most up to date satellite imagery for the region. Many of the buildings here were mapped using Maxar that was generally the most recent but it is no longer available to mappers. ESRI is better than Bing. But that is not the case over the whole of Zambia. Just check between the layers. It is the reason I think mapping buildings is pointless in Zambia, particularly for census purposes. I suggest you review your recent edits in this region.