Buildings that are placed together with modules such as Warehouses and Greenhouses (e.g., the building shown in the image below) cannot be stored individually.
If you want to remove these buildings—for example, to change from Special Build to Normal Build—you need to remove all objects within the Building Area using the "Remove All" option.
For details on Special Build, please refer to the official web manual.
If "Remove All" option does not work, please refer to the Q&A: 【Atelier Yumia】"There are objects that cannot be removed" appears and Remove All option does not work.