I want to setup, so they only harvest raw food resources when they drop below X in storage.
But clearly not working, so here are my settings, that I tough would fix it.
Where lies my error?

Set fields not be allowed to auto harvest.
https://prnt.sc/VUemNmMZbZji

Work priority settings. IMHO should not matter, but something is clearly wrong.
https://prnt.sc/VhdYI9vGtiKu

Set auto harvest only if below X, ( X = 500 )
https://prnt.sc/TMGNbM0KFfGc

Have over X amount RICE, but peons still go and harvest.
https://prnt.sc/61roBxZFqdvU

Even look at the Graph, X amount went never below set target.
https://prnt.sc/n1dj8_JbzC84

EDIT: Later in the game... Still set 2 fields to not harvest.
Set mod to only harvest if resource Y or Z is lower then X individually (X=500)
They are 2 separate manager orders, one for rice(Y) and one for potatoes(Z).
https://prnt.sc/77xEc3NABkSG

https://prnt.sc/dA320mstjiml