This happens with many games that have few available save slots, and it is usually easier to delete old saves after making a backup by creating a shortcut to the folder where you store them, to be able to open it without having to search for it again when necessary.
So an alternative would be to create a shortcut to the folder where Summer Clover stores the saves:
https://f95zone.to/threads/summer-clover-v1-11-connection.214008/post-14662382
C:\Users\<UserName>\AppData\LocalLow\Connection\SummerClover\Data\Saves
Where if the 12 available save slots are full, there will be within that folder 12 GameSave001/012.nson files that store those savegames, in addition to the saves that correspond to the Quick-Save (GameQuickSave001/012.nson) and the one that stores the game settings (Settings.json)
so make a backup of that Saves folder
compressing it inside a rar or zip with the compressor that you have installed on your PC, selecting it and opening the context menu of Windows Explorer.
And after making that backup to preserve them, you can delete the game saves, leaving only the last savegame to free up those few available save slots
and when you want to load an old save, select the corresponding backup compressed file, select extract here in the compressor's context menu, having also previously made a backup of your latest saves to be able to restore them again later, before overwriting them with the old ones.
