you must have mods with a densityHeight.xml in it
There are some mods reported in the comments that causes this. Additional FillTypes, Terrafarm, Grain Dryers
Viewing post in FS25 Riverbend Springs Multifruit comments
For some reasons, Giants, after increasing support to up to 64 fruits, decided that fs25 should have the same 6 channeld desity height xml. For that reason, any mod that adds bulk materials (that can be tipped on the ground), need a xml for that, and that xml is with 6 channels. For whatever reasons, the game decides to use only 6 channels, instead of the increased one used on a multifruit map and that causes overlaping...